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	<id>https://wiki.universitas.ro/index.php?action=history&amp;feed=atom&amp;title=E%3A14331</id>
	<title>E:14331 - Revision history</title>
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	<updated>2026-06-16T22:59:36Z</updated>
	<subtitle>Revision history for this page on the wiki</subtitle>
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	<entry>
		<id>https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=9474&amp;oldid=prev</id>
		<title>Andrei.Horvat at 07:42, 16 January 2024</title>
		<link rel="alternate" type="text/html" href="https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=9474&amp;oldid=prev"/>
		<updated>2024-01-16T07:42:18Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
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				&lt;col class=&quot;diff-content&quot; /&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 07:42, 16 January 2024&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l2&quot;&gt;Line 2:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 2:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&#039;&#039;Fie &#039;&#039;&amp;lt;math&amp;gt; n \ge2 &amp;lt;/math&amp;gt;&#039;&#039; un număr natural. Arătați că numărul &#039;&#039;&amp;lt;math&amp;gt; n^4 + n^2 + 3 &amp;lt;/math&amp;gt; &#039;&#039;nu poate fi scris ca &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;suma &lt;/del&gt;a &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;doua &lt;/del&gt;numere prime.&#039;&#039;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&#039;&#039;Fie &#039;&#039;&amp;lt;math&amp;gt; n \ge2 &amp;lt;/math&amp;gt;&#039;&#039; un număr natural. Arătați că numărul &#039;&#039;&amp;lt;math&amp;gt; n^4 + n^2 + 3 &amp;lt;/math&amp;gt; &#039;&#039;nu poate fi scris ca &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;sumă &lt;/ins&gt;a &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;două &lt;/ins&gt;numere prime.&#039;&#039;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Andrei.Horvat</name></author>
	</entry>
	<entry>
		<id>https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=9473&amp;oldid=prev</id>
		<title>Andrei.Horvat at 07:40, 16 January 2024</title>
		<link rel="alternate" type="text/html" href="https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=9473&amp;oldid=prev"/>
		<updated>2024-01-16T07:40:05Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr class=&quot;diff-title&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 07:40, 16 January 2024&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l8&quot;&gt;Line 8:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 8:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;Avem &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;&amp;lt;math&amp;gt;n^4 + n^2 + 3 = n^2(n^2+1) + 3 &amp;lt;/math&amp;gt;.&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/del&gt;Deoarece&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/del&gt;&amp;lt;math&amp;gt;n^2&amp;lt;/math&amp;gt; &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;și&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/del&gt;&amp;lt;math&amp;gt;n^2 + 1&amp;lt;/math&amp;gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/del&gt;sunt consecutive, produsul lor este un număr par și atunci &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;&amp;lt;math&amp;gt; n^4 + n^2 + 3&amp;lt;/math&amp;gt; &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;este număr impar. Presupunem că există două numere prime,&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/del&gt;și &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;&amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;astfel încât &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;&amp;lt;math&amp;gt;n^4 + n^2 + 3 = a + b.&amp;lt;/math&amp;gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;Din cele de mai sus unul dintre numere &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;&amp;lt;math&amp;gt;a &amp;lt;/math&amp;gt; &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;și &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;&amp;lt;math&amp;gt;b &amp;lt;/math&amp;gt; &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;trebuie să fie &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;&amp;lt;math&amp;gt;2&amp;lt;/math&amp;gt;. &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;Alegem &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;&amp;lt;math&amp;gt;a =2.&amp;lt;/math&amp;gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;Atunci, &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/del&gt;&amp;lt;math&amp;gt; n^4 + n^2 + 3 = (n^2 - n + 1)(n^2 + n + 1).&amp;lt;/math&amp;gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;Cum &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;&amp;lt;math&amp;gt;(n^2 - n + 1)&amp;lt;/math&amp;gt; &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;și&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/del&gt;&amp;lt;math&amp;gt;(n^2 + n + 1)&amp;lt;/math&amp;gt; &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;sunt mai mari ca &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;&amp;lt;math&amp;gt;1&amp;lt;/math&amp;gt; &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;în condițiile date, rezultă&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/del&gt;&amp;lt;math&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Avem &amp;lt;math&amp;gt;n^4 + n^2 + 3 = n^2(n^2+1) + 3 &amp;lt;/math&amp;gt;. Deoarece &amp;lt;math&amp;gt;n^2&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;n^2 + 1&amp;lt;/math&amp;gt; sunt consecutive, produsul lor este un număr par și atunci &amp;lt;math&amp;gt; n^4 + n^2 + 3&amp;lt;/math&amp;gt; este număr impar. Presupunem că există două numere prime, &amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; astfel încât &amp;lt;math&amp;gt;n^4 + n^2 + 3 = a + b.&amp;lt;/math&amp;gt; Din cele de mai sus unul dintre numere &amp;lt;math&amp;gt;a &amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b &amp;lt;/math&amp;gt; trebuie să fie &amp;lt;math&amp;gt;2&amp;lt;/math&amp;gt;.  &lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;b&amp;lt;/math&amp;gt; &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;nu este număr prim. Prin urmare, presupunerea făcută este falsă.&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt; &lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Alegem &amp;lt;math&amp;gt;a =2.&amp;lt;/math&amp;gt; Atunci, &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt; &lt;/ins&gt;&amp;lt;math &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;display=&quot;block&quot;&lt;/ins&gt;&amp;gt; n^4 + n^2 + 3 = (n^2 - n + 1)(n^2 + n + 1).&amp;lt;/math&amp;gt;Cum &amp;lt;math&amp;gt;(n^2 - n + 1)&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;(n^2 + n + 1)&amp;lt;/math&amp;gt; sunt mai mari ca &amp;lt;math&amp;gt;1&amp;lt;/math&amp;gt; în condițiile date, rezultă &amp;lt;math&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;b&amp;lt;/math&amp;gt; nu este număr prim. Prin urmare, presupunerea făcută este falsă.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Andrei.Horvat</name></author>
	</entry>
	<entry>
		<id>https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8610&amp;oldid=prev</id>
		<title>Teglas Bogdan at 21:19, 27 December 2023</title>
		<link rel="alternate" type="text/html" href="https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8610&amp;oldid=prev"/>
		<updated>2023-12-27T21:19:45Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr class=&quot;diff-title&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 21:19, 27 December 2023&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l8&quot;&gt;Line 8:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 8:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&#039;&#039;Avem &#039;&#039;&amp;lt;math&amp;gt;n^4 + n^2 + 3 = n^2(n^2+1) + 3 &amp;lt;/math&amp;gt;.&#039;&#039; Deoarece&#039;&#039; &amp;lt;math&amp;gt;n^2&amp;lt;/math&amp;gt; &#039;&#039;și&#039;&#039; &amp;lt;math&amp;gt;n^2 + 1&amp;lt;/math&amp;gt;&#039;&#039; sunt consecutive, produsul lor este un număr par și atunci&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&lt;/del&gt;&#039;&#039;&amp;lt;math&amp;gt; n^4 + n^2 + 3&amp;lt;/math&amp;gt; &#039;&#039;este număr impar. Presupunem că există două numere prime,&#039;&#039;&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt;&#039;&#039; și &#039;&#039;&amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; &#039;&#039;astfel încât &#039;&#039;&amp;lt;math&amp;gt;n^4 + n^2 + 3 = a + b.&amp;lt;/math&amp;gt;&#039;&#039;Din cele de mai sus unul dintre numere &#039;&#039;&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; &#039;&#039;și &#039;&#039;&amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; &#039;&#039;trebuie să fie&#039;&#039;&amp;lt;math&amp;gt;2&amp;lt;/math&amp;gt;. &#039;&#039;Alegem &#039;&#039;&amp;lt;math&amp;gt;a=2.&amp;lt;/math&amp;gt;&#039;&#039;Atunci, &#039;&#039; &amp;lt;math&amp;gt; n^4 + n^2 + 3 = (n^2 - n + 1)(n^2 + n + 1).&amp;lt;/math&amp;gt;&#039;&#039;Cum &#039;&#039;&amp;lt;math&amp;gt;(n^2 - n + 1)&amp;lt;/math&amp;gt; &#039;&#039;și&#039;&#039; &amp;lt;math&amp;gt;(n^2 + n + 1)&amp;lt;/math&amp;gt; &#039;&#039;sunt mai mari ca &#039;&#039;&amp;lt;math&amp;gt;1&amp;lt;/math&amp;gt; &#039;&#039;în condițiile date, rezultă&#039;&#039; &amp;lt;math&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&#039;&#039;Avem &#039;&#039;&amp;lt;math&amp;gt;n^4 + n^2 + 3 = n^2(n^2+1) + 3 &amp;lt;/math&amp;gt;.&#039;&#039; Deoarece&#039;&#039; &amp;lt;math&amp;gt;n^2&amp;lt;/math&amp;gt; &#039;&#039;și&#039;&#039; &amp;lt;math&amp;gt;n^2 + 1&amp;lt;/math&amp;gt;&#039;&#039; sunt consecutive, produsul lor este un număr par și atunci &#039;&#039;&amp;lt;math&amp;gt; n^4 + n^2 + 3&amp;lt;/math&amp;gt; &#039;&#039;este număr impar. Presupunem că există două numere prime,&#039;&#039;&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt;&#039;&#039; și &#039;&#039;&amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; &#039;&#039;astfel încât &#039;&#039;&amp;lt;math&amp;gt;n^4 + n^2 + 3 = a + b.&amp;lt;/math&amp;gt;&#039;&#039;Din cele de mai sus unul dintre numere &#039;&#039;&amp;lt;math&amp;gt;a &amp;lt;/math&amp;gt; &#039;&#039;și &#039;&#039;&amp;lt;math&amp;gt;b &amp;lt;/math&amp;gt; &#039;&#039;trebuie să fie &#039;&#039;&amp;lt;math&amp;gt;2&amp;lt;/math&amp;gt;. &#039;&#039;Alegem &#039;&#039;&amp;lt;math&amp;gt;a =2.&amp;lt;/math&amp;gt;&#039;&#039;Atunci, &#039;&#039; &amp;lt;math&amp;gt; n^4 + n^2 + 3 = (n^2 - n + 1)(n^2 + n + 1).&amp;lt;/math&amp;gt;&#039;&#039;Cum &#039;&#039;&amp;lt;math&amp;gt;(n^2 - n + 1)&amp;lt;/math&amp;gt; &#039;&#039;și&#039;&#039; &amp;lt;math&amp;gt;(n^2 + n + 1)&amp;lt;/math&amp;gt; &#039;&#039;sunt mai mari ca &#039;&#039;&amp;lt;math&amp;gt;1&amp;lt;/math&amp;gt; &#039;&#039;în condițiile date, rezultă&#039;&#039; &amp;lt;math&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;b&amp;lt;/math&amp;gt; &amp;#039;&amp;#039;nu este număr prim. Prin urmare, presupunerea făcută este falsă.&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;b&amp;lt;/math&amp;gt; &amp;#039;&amp;#039;nu este număr prim. Prin urmare, presupunerea făcută este falsă.&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Teglas Bogdan</name></author>
	</entry>
	<entry>
		<id>https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8609&amp;oldid=prev</id>
		<title>Teglas Bogdan at 21:18, 27 December 2023</title>
		<link rel="alternate" type="text/html" href="https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8609&amp;oldid=prev"/>
		<updated>2023-12-27T21:18:30Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr class=&quot;diff-title&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 21:18, 27 December 2023&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l8&quot;&gt;Line 8:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 8:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&#039;&#039;Avem &#039;&#039;&amp;lt;math&amp;gt;n^4 + n^2 + 3 = n^2(n^2+1) + 3 &amp;lt;/math&amp;gt;.&#039;&#039; Deoarece&#039;&#039; &amp;lt;math&amp;gt;n^2&amp;lt;/math&amp;gt; &#039;&#039;și&#039;&#039; &amp;lt;math&amp;gt;n^2 + 1&amp;lt;/math&amp;gt;&#039;&#039; sunt consecutive, produsul lor este un număr par și atunci&#039;&#039;&#039;&amp;lt;math&amp;gt; n^4 + n^2 + 3&amp;lt;/math&amp;gt; &#039;&#039;este număr impar. Presupunem că există două numere prime,&#039;&#039;&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt;&#039;&#039; și &#039;&#039;&amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; &#039;&#039;astfel încât &#039;&#039;&amp;lt;math&amp;gt;n^4 + n^2 + 3 = a + b.&amp;lt;/math&amp;gt;&#039;&#039;Din cele de mai sus unul dintre numere &#039;&#039;&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; &#039;&#039;și &#039;&#039;&amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; &#039;&#039;trebuie să fie&#039;&#039;&amp;lt;math&amp;gt;2&amp;lt;/math&amp;gt;. &#039;&#039;Alegem &#039;&#039;&amp;lt;math&amp;gt;a=2.&amp;lt;/math&amp;gt;&#039;&#039;Atunci,&#039;&#039; &amp;lt;math&amp;gt; n^4 + n^2 + 3 = (n^2 - n + 1)(n^2 + n + 1).&amp;lt;/math&amp;gt;&#039;&#039;Cum &#039;&#039;&amp;lt;math&amp;gt;(n^2 - n + 1)&amp;lt;/math&amp;gt; &#039;&#039;și&#039;&#039; &amp;lt;math&amp;gt;(n^2 + n + 1)&amp;lt;/math&amp;gt; &#039;&#039;sunt mai mari ca &#039;&#039;&amp;lt;math&amp;gt;1&amp;lt;/math&amp;gt; &#039;&#039;în condițiile date, rezultă&#039;&#039; &amp;lt;math&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&#039;&#039;Avem &#039;&#039;&amp;lt;math&amp;gt;n^4 + n^2 + 3 = n^2(n^2+1) + 3 &amp;lt;/math&amp;gt;.&#039;&#039; Deoarece&#039;&#039; &amp;lt;math&amp;gt;n^2&amp;lt;/math&amp;gt; &#039;&#039;și&#039;&#039; &amp;lt;math&amp;gt;n^2 + 1&amp;lt;/math&amp;gt;&#039;&#039; sunt consecutive, produsul lor este un număr par și atunci&#039;&#039;&#039;&amp;lt;math&amp;gt; n^4 + n^2 + 3&amp;lt;/math&amp;gt; &#039;&#039;este număr impar. Presupunem că există două numere prime,&#039;&#039;&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt;&#039;&#039; și &#039;&#039;&amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; &#039;&#039;astfel încât &#039;&#039;&amp;lt;math&amp;gt;n^4 + n^2 + 3 = a + b.&amp;lt;/math&amp;gt;&#039;&#039;Din cele de mai sus unul dintre numere &#039;&#039;&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; &#039;&#039;și &#039;&#039;&amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; &#039;&#039;trebuie să fie&#039;&#039;&amp;lt;math&amp;gt;2&amp;lt;/math&amp;gt;. &#039;&#039;Alegem &#039;&#039;&amp;lt;math&amp;gt;a=2.&amp;lt;/math&amp;gt;&#039;&#039;Atunci, &#039;&#039; &amp;lt;math&amp;gt; n^4 + n^2 + 3 = (n^2 - n + 1)(n^2 + n + 1).&amp;lt;/math&amp;gt;&#039;&#039;Cum &#039;&#039;&amp;lt;math&amp;gt;(n^2 - n + 1)&amp;lt;/math&amp;gt; &#039;&#039;și&#039;&#039; &amp;lt;math&amp;gt;(n^2 + n + 1)&amp;lt;/math&amp;gt; &#039;&#039;sunt mai mari ca &#039;&#039;&amp;lt;math&amp;gt;1&amp;lt;/math&amp;gt; &#039;&#039;în condițiile date, rezultă&#039;&#039; &amp;lt;math&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;b&amp;lt;/math&amp;gt; &amp;#039;&amp;#039;nu este număr prim. Prin urmare, presupunerea făcută este falsă.&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;b&amp;lt;/math&amp;gt; &amp;#039;&amp;#039;nu este număr prim. Prin urmare, presupunerea făcută este falsă.&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Teglas Bogdan</name></author>
	</entry>
	<entry>
		<id>https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8608&amp;oldid=prev</id>
		<title>Teglas Bogdan at 21:18, 27 December 2023</title>
		<link rel="alternate" type="text/html" href="https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8608&amp;oldid=prev"/>
		<updated>2023-12-27T21:18:01Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr class=&quot;diff-title&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 21:18, 27 December 2023&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l2&quot;&gt;Line 2:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 2:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&#039;&#039;Fie &amp;lt;math&amp;gt; n \ge2 &amp;lt;/math&amp;gt; un număr natural. Arătați că numărul &amp;lt;math&amp;gt; n^4 + n^2 + 3 &amp;lt;/math&amp;gt; nu poate fi scris ca suma a doua numere prime.&#039;&#039;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&#039;&#039;Fie &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;&amp;lt;math&amp;gt; n \ge2 &amp;lt;/math&amp;gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/ins&gt;un număr natural. Arătați că numărul &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;&amp;lt;math&amp;gt; n^4 + n^2 + 3 &amp;lt;/math&amp;gt; &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;nu poate fi scris ca suma a doua numere prime.&#039;&#039;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l8&quot;&gt;Line 8:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 8:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Avem &amp;lt;math&amp;gt;n^4 + n^2 + 3 = n^2(n^2+1) + 3 &amp;lt;/math&amp;gt;. Deoarece &amp;lt;math&amp;gt;n^2&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;n^2 + 1&amp;lt;/math&amp;gt; sunt consecutive, produsul lor este un număr par și atunci&amp;lt;math&amp;gt; n^4 + n^2 + 3&amp;lt;/math&amp;gt; este număr impar. Presupunem că există două numere prime,&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; astfel încât &amp;lt;math&amp;gt;n^4 + n^2 + 3 = a + b.&amp;lt;/math&amp;gt;Din cele de mai sus unul dintre numere &amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; trebuie să fie&amp;lt;math&amp;gt;2&amp;lt;/math&amp;gt;. Alegem &amp;lt;math&amp;gt;a=2.&amp;lt;/math&amp;gt;Atunci, &amp;lt;math&amp;gt; n^4 + n^2 + 3 = (n^2 - n + 1)(n^2 + n + 1).&amp;lt;/math&amp;gt;Cum &amp;lt;math&amp;gt;(n^2 - n + 1)&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;(n^2 + n + 1)&amp;lt;/math&amp;gt; sunt mai mari &amp;lt;math&amp;gt;1&amp;lt;/math&amp;gt; în condițiile date, rezultă &amp;lt;math&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;Avem &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;&amp;lt;math&amp;gt;n^4 + n^2 + 3 = n^2(n^2+1) + 3 &amp;lt;/math&amp;gt;.&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/ins&gt;Deoarece&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/ins&gt;&amp;lt;math&amp;gt;n^2&amp;lt;/math&amp;gt; &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;și&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/ins&gt;&amp;lt;math&amp;gt;n^2 + 1&amp;lt;/math&amp;gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/ins&gt;sunt consecutive, produsul lor este un număr par și atunci&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&#039;&lt;/ins&gt;&amp;lt;math&amp;gt; n^4 + n^2 + 3&amp;lt;/math&amp;gt; &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;este număr impar. Presupunem că există două numere prime,&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/ins&gt;și &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;&amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;astfel încât &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;&amp;lt;math&amp;gt;n^4 + n^2 + 3 = a + b.&amp;lt;/math&amp;gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;Din cele de mai sus unul dintre numere &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;și &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;&amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;trebuie să fie&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;&amp;lt;math&amp;gt;2&amp;lt;/math&amp;gt;. &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;Alegem &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;&amp;lt;math&amp;gt;a=2.&amp;lt;/math&amp;gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;Atunci,&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/ins&gt;&amp;lt;math&amp;gt; n^4 + n^2 + 3 = (n^2 - n + 1)(n^2 + n + 1).&amp;lt;/math&amp;gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;Cum &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;&amp;lt;math&amp;gt;(n^2 - n + 1)&amp;lt;/math&amp;gt; &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;și&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/ins&gt;&amp;lt;math&amp;gt;(n^2 + n + 1)&amp;lt;/math&amp;gt; &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;sunt mai mari &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;ca &#039;&#039;&lt;/ins&gt;&amp;lt;math&amp;gt;1&amp;lt;/math&amp;gt; &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;în condițiile date, rezultă&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039; &lt;/ins&gt;&amp;lt;math&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;b&amp;lt;/math&amp;gt; nu este număr prim. Prin urmare, presupunerea făcută este falsă.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;b&amp;lt;/math&amp;gt; &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;nu este număr prim. Prin urmare, presupunerea făcută este falsă.&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&#039;&#039;&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Teglas Bogdan</name></author>
	</entry>
	<entry>
		<id>https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8601&amp;oldid=prev</id>
		<title>Teglas Bogdan at 20:57, 27 December 2023</title>
		<link rel="alternate" type="text/html" href="https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8601&amp;oldid=prev"/>
		<updated>2023-12-27T20:57:58Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr class=&quot;diff-title&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 20:57, 27 December 2023&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l2&quot;&gt;Line 2:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 2:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&#039;&#039;Fie &amp;lt;math&amp;gt; n &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&amp;gt;= 2 &lt;/del&gt;&amp;lt;/math&amp;gt; un număr natural. Arătați că numărul &amp;lt;math&amp;gt; n^4 + n^2 + 3 &amp;lt;/math&amp;gt; nu poate fi scris ca suma a doua numere prime.&#039;&#039;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&#039;&#039;Fie &amp;lt;math&amp;gt; n &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;\ge2 &lt;/ins&gt;&amp;lt;/math&amp;gt; un număr natural. Arătați că numărul &amp;lt;math&amp;gt; n^4 + n^2 + 3 &amp;lt;/math&amp;gt; nu poate fi scris ca suma a doua numere prime.&#039;&#039;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Teglas Bogdan</name></author>
	</entry>
	<entry>
		<id>https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8597&amp;oldid=prev</id>
		<title>Teglas Bogdan at 20:36, 27 December 2023</title>
		<link rel="alternate" type="text/html" href="https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8597&amp;oldid=prev"/>
		<updated>2023-12-27T20:36:35Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr class=&quot;diff-title&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 20:36, 27 December 2023&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l4&quot;&gt;Line 4:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 4:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;Fie &amp;lt;math&amp;gt; n &amp;gt;= 2 &amp;lt;/math&amp;gt; un număr natural. Arătați că numărul &amp;lt;math&amp;gt; n^4 + n^2 + 3 &amp;lt;/math&amp;gt; nu poate fi scris ca suma a doua numere prime.&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;Fie &amp;lt;math&amp;gt; n &amp;gt;= 2 &amp;lt;/math&amp;gt; un număr natural. Arătați că numărul &amp;lt;math&amp;gt; n^4 + n^2 + 3 &amp;lt;/math&amp;gt; nu poate fi scris ca suma a doua numere prime.&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;Soluție.&amp;#039;&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;Soluție.&amp;#039;&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Teglas Bogdan</name></author>
	</entry>
	<entry>
		<id>https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8596&amp;oldid=prev</id>
		<title>Teglas Bogdan at 20:36, 27 December 2023</title>
		<link rel="alternate" type="text/html" href="https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8596&amp;oldid=prev"/>
		<updated>2023-12-27T20:36:21Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 20:36, 27 December 2023&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l1&quot;&gt;Line 1:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 1:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;E:14.331 (Cristina Vijdeluc și Mihai Vijdeluc)&amp;#039;&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;E:14.331 (Cristina Vijdeluc și Mihai Vijdeluc)&amp;#039;&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;Fie &amp;lt;math&amp;gt; n &amp;gt;= 2 &amp;lt;/math&amp;gt; un număr natural. Arătați că numărul &amp;lt;math&amp;gt; n^4 + n^2 + 3 &amp;lt;/math&amp;gt; nu poate fi scris ca suma a doua numere prime.&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;Fie &amp;lt;math&amp;gt; n &amp;gt;= 2 &amp;lt;/math&amp;gt; un număr natural. Arătați că numărul &amp;lt;math&amp;gt; n^4 + n^2 + 3 &amp;lt;/math&amp;gt; nu poate fi scris ca suma a doua numere prime.&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;Soluție.&amp;#039;&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;Soluție.&amp;#039;&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br /&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Avem &amp;lt;math&amp;gt;n^4 + n^2 + 3 = n^2(n^2+1) + 3 &amp;lt;/math&amp;gt;. Deoarece &amp;lt;math&amp;gt;n^2&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;n^2 + 1&amp;lt;/math&amp;gt; sunt consecutive, produsul lor este un număr par și atunci&amp;lt;math&amp;gt; n^4 + n^2 + 3&amp;lt;/math&amp;gt; este număr impar. Presupunem că există două numere prime,&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; astfel încât &amp;lt;math&amp;gt;n^4 + n^2 + 3 = a + b.&amp;lt;/math&amp;gt;Din cele de mai sus unul dintre numere &amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; trebuie să fie&amp;lt;math&amp;gt;2&amp;lt;/math&amp;gt;. Alegem &amp;lt;math&amp;gt;a=2.&amp;lt;/math&amp;gt;Atunci, &amp;lt;math&amp;gt; n^4 + n^2 + 3 = (n^2 - n + 1)(n^2 + n + 1).&amp;lt;/math&amp;gt;Cum &amp;lt;math&amp;gt;(n^2 - n + 1)&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;(n^2 + n + 1)&amp;lt;/math&amp;gt; sunt mai mari &amp;lt;math&amp;gt;1&amp;lt;/math&amp;gt; în condițiile date, rezultă &amp;lt;math&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Avem &amp;lt;math&amp;gt;n^4 + n^2 + 3 = n^2(n^2+1) + 3 &amp;lt;/math&amp;gt;. Deoarece &amp;lt;math&amp;gt;n^2&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;n^2 + 1&amp;lt;/math&amp;gt; sunt consecutive, produsul lor este un număr par și atunci&amp;lt;math&amp;gt; n^4 + n^2 + 3&amp;lt;/math&amp;gt; este număr impar. Presupunem că există două numere prime,&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; astfel încât &amp;lt;math&amp;gt;n^4 + n^2 + 3 = a + b.&amp;lt;/math&amp;gt;Din cele de mai sus unul dintre numere &amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; trebuie să fie&amp;lt;math&amp;gt;2&amp;lt;/math&amp;gt;. Alegem &amp;lt;math&amp;gt;a=2.&amp;lt;/math&amp;gt;Atunci, &amp;lt;math&amp;gt; n^4 + n^2 + 3 = (n^2 - n + 1)(n^2 + n + 1).&amp;lt;/math&amp;gt;Cum &amp;lt;math&amp;gt;(n^2 - n + 1)&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;(n^2 + n + 1)&amp;lt;/math&amp;gt; sunt mai mari &amp;lt;math&amp;gt;1&amp;lt;/math&amp;gt; în condițiile date, rezultă &amp;lt;math&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;b&amp;lt;/math&amp;gt; nu este număr prim. Prin urmare, presupunerea făcută este falsă.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;b&amp;lt;/math&amp;gt; nu este număr prim. Prin urmare, presupunerea făcută este falsă.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Teglas Bogdan</name></author>
	</entry>
	<entry>
		<id>https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8595&amp;oldid=prev</id>
		<title>Teglas Bogdan at 20:35, 27 December 2023</title>
		<link rel="alternate" type="text/html" href="https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8595&amp;oldid=prev"/>
		<updated>2023-12-27T20:35:51Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 20:35, 27 December 2023&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l1&quot;&gt;Line 1:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 1:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;E:14.331 (Cristina Vijdeluc și Mihai Vijdeluc)&amp;#039;&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;E:14.331 (Cristina Vijdeluc și Mihai Vijdeluc)&amp;#039;&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;/&lt;/ins&gt;&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;Fie &amp;lt;math&amp;gt; n &amp;gt;= 2 &amp;lt;/math&amp;gt; un număr natural. Arătați că numărul &amp;lt;math&amp;gt; n^4 + n^2 + 3 &amp;lt;/math&amp;gt; nu poate fi scris ca suma a doua numere prime.&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;Fie &amp;lt;math&amp;gt; n &amp;gt;= 2 &amp;lt;/math&amp;gt; un număr natural. Arătați că numărul &amp;lt;math&amp;gt; n^4 + n^2 + 3 &amp;lt;/math&amp;gt; nu poate fi scris ca suma a doua numere prime.&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;/&lt;/ins&gt;&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;Soluție.&amp;#039;&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;Soluție.&amp;#039;&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;/&lt;/ins&gt;&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Avem &amp;lt;math&amp;gt;n^4 + n^2 + 3 = n^2(n^2+1) + 3 &amp;lt;/math&amp;gt;. Deoarece &amp;lt;math&amp;gt;n^2&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;n^2 + 1&amp;lt;/math&amp;gt; sunt consecutive, produsul lor este un număr par și atunci&amp;lt;math&amp;gt; n^4 + n^2 + 3&amp;lt;/math&amp;gt; este număr impar. Presupunem că există două numere prime,&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; astfel încât &amp;lt;math&amp;gt;n^4 + n^2 + 3 = a + b.&amp;lt;/math&amp;gt;Din cele de mai sus unul dintre numere &amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; trebuie să fie&amp;lt;math&amp;gt;2&amp;lt;/math&amp;gt;. Alegem &amp;lt;math&amp;gt;a=2.&amp;lt;/math&amp;gt;Atunci, &amp;lt;math&amp;gt; n^4 + n^2 + 3 = (n^2 - n + 1)(n^2 + n + 1).&amp;lt;/math&amp;gt;Cum &amp;lt;math&amp;gt;(n^2 - n + 1)&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;(n^2 + n + 1)&amp;lt;/math&amp;gt; sunt mai mari &amp;lt;math&amp;gt;1&amp;lt;/math&amp;gt; în condițiile date, rezultă &amp;lt;math&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Avem &amp;lt;math&amp;gt;n^4 + n^2 + 3 = n^2(n^2+1) + 3 &amp;lt;/math&amp;gt;. Deoarece &amp;lt;math&amp;gt;n^2&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;n^2 + 1&amp;lt;/math&amp;gt; sunt consecutive, produsul lor este un număr par și atunci&amp;lt;math&amp;gt; n^4 + n^2 + 3&amp;lt;/math&amp;gt; este număr impar. Presupunem că există două numere prime,&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; astfel încât &amp;lt;math&amp;gt;n^4 + n^2 + 3 = a + b.&amp;lt;/math&amp;gt;Din cele de mai sus unul dintre numere &amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; trebuie să fie&amp;lt;math&amp;gt;2&amp;lt;/math&amp;gt;. Alegem &amp;lt;math&amp;gt;a=2.&amp;lt;/math&amp;gt;Atunci, &amp;lt;math&amp;gt; n^4 + n^2 + 3 = (n^2 - n + 1)(n^2 + n + 1).&amp;lt;/math&amp;gt;Cum &amp;lt;math&amp;gt;(n^2 - n + 1)&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;(n^2 + n + 1)&amp;lt;/math&amp;gt; sunt mai mari &amp;lt;math&amp;gt;1&amp;lt;/math&amp;gt; în condițiile date, rezultă &amp;lt;math&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;b&amp;lt;/math&amp;gt; nu este număr prim. Prin urmare, presupunerea făcută este falsă.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;b&amp;lt;/math&amp;gt; nu este număr prim. Prin urmare, presupunerea făcută este falsă.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Teglas Bogdan</name></author>
	</entry>
	<entry>
		<id>https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8594&amp;oldid=prev</id>
		<title>Teglas Bogdan at 20:34, 27 December 2023</title>
		<link rel="alternate" type="text/html" href="https://wiki.universitas.ro/index.php?title=E:14331&amp;diff=8594&amp;oldid=prev"/>
		<updated>2023-12-27T20:34:43Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
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				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 20:34, 27 December 2023&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l5&quot;&gt;Line 5:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 5:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;Soluție.&amp;#039;&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;#039;&amp;#039;&amp;#039;Soluție.&amp;#039;&amp;#039;&amp;#039;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&amp;lt;br&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Avem &amp;lt;math &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;display&lt;/del&gt;&amp;gt;n^4 + n^2 + 3 = &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;\left (&lt;/del&gt;n^2(n^2+1) + 3&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;) &lt;/del&gt;&amp;lt;/math&amp;gt;. Deoarece &amp;lt;math&amp;gt;n^2&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;n^2 + 1&amp;lt;/math&amp;gt; sunt consecutive, produsul lor este un număr par și atunci&amp;lt;math&amp;gt; n^4 + n^2 + 3&amp;lt;/math&amp;gt; este număr impar. Presupunem că există două numere prime,&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; astfel încât &amp;lt;math&amp;gt;n^4 + n^2 + 3 = a + b.&amp;lt;/math&amp;gt;Din cele de mai sus unul dintre numere &amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; trebuie să fie&amp;lt;math&amp;gt;2&amp;lt;/math&amp;gt;. Alegem &amp;lt;math&amp;gt;a=2.&amp;lt;/math&amp;gt;Atunci, &amp;lt;math&amp;gt; n^4 + n^2 + 3 = (n^2 - n + 1)(n^2 + n + 1).&amp;lt;/math&amp;gt;Cum &amp;lt;math&amp;gt;(n^2 - n + 1)&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;(n^2 + n + 1)&amp;lt;/math&amp;gt; sunt mai mari &amp;lt;math&amp;gt;1&amp;lt;/math&amp;gt; în condițiile date, rezultă &amp;lt;math&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Avem &amp;lt;math&amp;gt;n^4 + n^2 + 3 = n^2(n^2+1) + 3 &amp;lt;/math&amp;gt;. Deoarece &amp;lt;math&amp;gt;n^2&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;n^2 + 1&amp;lt;/math&amp;gt; sunt consecutive, produsul lor este un număr par și atunci&amp;lt;math&amp;gt; n^4 + n^2 + 3&amp;lt;/math&amp;gt; este număr impar. Presupunem că există două numere prime,&amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; astfel încât &amp;lt;math&amp;gt;n^4 + n^2 + 3 = a + b.&amp;lt;/math&amp;gt;Din cele de mai sus unul dintre numere &amp;lt;math&amp;gt;a&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;b&amp;lt;/math&amp;gt; trebuie să fie&amp;lt;math&amp;gt;2&amp;lt;/math&amp;gt;. Alegem &amp;lt;math&amp;gt;a=2.&amp;lt;/math&amp;gt;Atunci, &amp;lt;math&amp;gt; n^4 + n^2 + 3 = (n^2 - n + 1)(n^2 + n + 1).&amp;lt;/math&amp;gt;Cum &amp;lt;math&amp;gt;(n^2 - n + 1)&amp;lt;/math&amp;gt; și &amp;lt;math&amp;gt;(n^2 + n + 1)&amp;lt;/math&amp;gt; sunt mai mari &amp;lt;math&amp;gt;1&amp;lt;/math&amp;gt; în condițiile date, rezultă &amp;lt;math&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;b&amp;lt;/math&amp;gt; nu este număr prim. Prin urmare, presupunerea făcută este falsă.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;b&amp;lt;/math&amp;gt; nu este număr prim. Prin urmare, presupunerea făcută este falsă.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Teglas Bogdan</name></author>
	</entry>
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