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    <title>MaplePrimes - comments on Post, Using extrema</title>
    <link>http://www.mapleprimes.com/posts/37995-Using-Extrema</link>
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    <lastBuildDate>Thu, 11 Jun 2026 02:48:57 GMT</lastBuildDate>
    <pubDate>Thu, 11 Jun 2026 02:48:57 GMT</pubDate>
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    <description>The latest comments added to the Post, Using extrema</description>
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      <url>http://www.mapleprimes.com/images/mapleprimeswhite.jpg</url>
      <title>MaplePrimes - comments on Post, Using extrema</title>
      <link>http://www.mapleprimes.com/posts/37995-Using-Extrema</link>
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    <item>
      <title>This might be what you are</title>
      <link>http://www.mapleprimes.com/posts/37995-Using-Extrema?ref=Feed:MaplePrimes:Using extrema:Comments#comment67823</link>
      <itunes:summary>This might be what you are looking for:
&lt;pre&gt;
&gt; restart; with(Student[Calculus1]);
 f := proc (x) options operator, arrow; 3*x^4-4*x^3 end proc;

                                         4      3
                            f := x -&gt; 3 x  - 4 x 

&gt; ExtremePoints(f(x), x = -1 .. 2); map(f, %);

                                 [-1, 1, 2]
                                 [7, -1, 16]
&gt; plot(f, -1 .. 2);
&lt;/pre&gt;
&lt;a href='http://www.mapleprimes.com/viewfile/3147'&gt;&lt;img src='http://www.mapleprimes.com/files/97_extrema.jpeg' alt='97_extrema.jpeg'&gt;&lt;/a&gt;
Regards,
--Jean-Marc</itunes:summary>
      <description>The latest comments added to the Post, Using extrema</description>
      <guid>67823</guid>
      <pubDate>Tue, 27 Jan 2009 11:00:25 Z</pubDate>
      <itunes:author>gulliet</itunes:author>
      <author>gulliet</author>
    </item>
    <item>
      <title>ExtremePoints</title>
      <link>http://www.mapleprimes.com/posts/37995-Using-Extrema?ref=Feed:MaplePrimes:Using extrema:Comments#comment67824</link>
      <itunes:summary>&lt;pre&gt;
Student:-Calculus1:-ExtremePoints(3*x^4 - 4*x^3,-1..2);

                              [-1, 1, 2]
&lt;/pre&gt;
&lt;p&gt;However, that answer is wrong if you need global extrema. The function has a minimum at x=1 and a maximum at x=2 on this interval, which can be found by evaluating&lt;/p&gt;
&lt;pre&gt;
map(x-&amp;gt;3*x^4-4*x^3,%);

                             [7, -1, 16]
&lt;/pre&gt;
&lt;p&gt;Alec&lt;/p&gt;</itunes:summary>
      <description>The latest comments added to the Post, Using extrema</description>
      <guid>67824</guid>
      <pubDate>Tue, 27 Jan 2009 11:04:18 Z</pubDate>
      <itunes:author>alec</itunes:author>
      <author>alec</author>
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    <item>
      <title>Request for a simpler answer</title>
      <link>http://www.mapleprimes.com/posts/37995-Using-Extrema?ref=Feed:MaplePrimes:Using extrema:Comments#comment67822</link>
      <itunes:summary>&lt;p style="margin: 0in 0in 0pt"&gt;&amp;nbsp;&lt;/p&gt;
&lt;p style="margin: 0in 0in 0pt"&gt;&amp;nbsp;&lt;/p&gt;
&lt;p style="margin: 0in 0in 0pt"&gt;&amp;nbsp;&lt;/p&gt;
&lt;p&gt;&lt;span style="font-size: 14pt; font-family: &amp;quot;Times New Roman&amp;quot;; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 'Times New Roman'; mso-text-raise: -3.5pt; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA"&gt;I don't want to appear ungrateful, but I was hoping for a simpler answer.&amp;nbsp; For example,&lt;/span&gt;&lt;/p&gt;
&lt;p&gt;&lt;span style="font-size: 14pt; font-family: &amp;quot;Times New Roman&amp;quot;; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 'Times New Roman'; mso-text-raise: -3.5pt; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA"&gt;
&lt;p class="MsoNormal" style="margin: 0in 0in 0pt"&gt;&lt;span class="MapleInput"&gt;&lt;span style="font-size: 12pt; font-family: 'Courier New'"&gt;&lt;strong&gt;&lt;font color="#ff0000"&gt;extrema(3*x^4-4*x^3,{},x);&lt;/font&gt;&lt;/strong&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;
&lt;p class="MsoNormal" style="margin: 0in 0in 0pt"&gt;&amp;nbsp;&lt;/p&gt;
&lt;p class="MsoNormal" style="margin: 0in 0in 0pt"&gt;&lt;span class="MapleInput"&gt;&lt;span style="font-size: 12pt; font-family: 'Courier New'"&gt;&lt;strong&gt;yields &lt;/strong&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;
&lt;p class="MsoNormal" style="margin: 0in 0in 0pt"&gt;&lt;span class="MapleInput"&gt;&lt;span style="font-size: 12pt; font-family: 'Courier New'"&gt;&lt;strong&gt;&amp;nbsp;&lt;/strong&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;
&lt;p class="MsoNormal" style="margin: 0in 0in 0pt"&gt;&lt;span class="MapleInput"&gt;&lt;span style="font-size: 12pt; font-family: 'Courier New'"&gt;&lt;strong&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; {-1, 0}&lt;/strong&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;
&lt;p class="MsoNormal" style="margin: 0in 0in 0pt"&gt;&amp;nbsp;&lt;/p&gt;
&lt;p class="MsoNormal" style="margin: 0in 0in 0pt"&gt;&lt;span class="MapleInput"&gt;&lt;span style="font-size: 12pt; font-family: 'Courier New'"&gt;&lt;strong&gt;It would be nice if this command could be modified to consider the endpoints.&lt;/strong&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;
&lt;p class="MsoNormal" style="margin: 0in 0in 0pt"&gt;&amp;nbsp;&lt;/p&gt;
&lt;p class="MsoNormal" style="margin: 0in 0in 0pt"&gt;&amp;nbsp;&lt;/p&gt;
&lt;p class="MsoNormal" style="margin: 0in 0in 0pt"&gt;&amp;nbsp;&lt;/p&gt;
&lt;/span&gt;&lt;/p&gt;
&lt;p&gt;&lt;span style="font-size: 14pt; font-family: &amp;quot;Times New Roman&amp;quot;; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 'Times New Roman'; mso-text-raise: -3.5pt; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA"&gt;&lt;v:shape id="_x0000_i1025" style="width: 42pt; height: 15pt" type="#_x0000_t75"&gt;&lt;v:imagedata o:title="" src="file:///C:/DOCUME~1/Owner/LOCALS~1/Temp/msoclip1/01/clip_image001.wmz"&gt;&lt;/v:imagedata&gt;&lt;/v:shape&gt;&lt;/span&gt;&lt;/p&gt;
&lt;p&gt;&amp;nbsp;&lt;/p&gt;</itunes:summary>
      <description>The latest comments added to the Post, Using extrema</description>
      <guid>67822</guid>
      <pubDate>Tue, 27 Jan 2009 11:36:24 Z</pubDate>
      <itunes:author>alla</itunes:author>
      <author>alla</author>
    </item>
    <item>
      <title>minimize, maximize</title>
      <link>http://www.mapleprimes.com/posts/37995-Using-Extrema?ref=Feed:MaplePrimes:Using extrema:Comments#comment82269</link>
      <itunes:summary>&lt;p&gt;If ExtremePoints are too complicated, one can use minimize and maximize. For example,&lt;/p&gt;
&lt;pre&gt;
f:=3*x^4-4*x^3:
(minimize,maximize)(f,x=-1..2,location);

               -1, {[{x = 1}, -1]}, 16, {[{x = 2}, 16]}
&lt;/pre&gt;
&lt;p&gt;But that may be erroneous in cases with several local minimums and maximums (as well as ExtremePoints). So it is always a good idea to look at the plot at least.&lt;/p&gt;
&lt;p&gt;Alec&lt;/p&gt;</itunes:summary>
      <description>The latest comments added to the Post, Using extrema</description>
      <guid>82269</guid>
      <pubDate>Tue, 27 Jan 2009 12:08:00 Z</pubDate>
      <itunes:author>alec</itunes:author>
      <author>alec</author>
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