document.write( "Question 1181193: Find the number in the interval [ - 2, 2 ] so that the difference of the
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Algebra.Com's Answer #811080 by ikleyn(53751) $\"\"$ $\"About$

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\n" ); document.write( "Find the number in the interval [ - 2, 2 ] so that the difference of the
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\n" ); document.write( "\n" ); document.write( "            The solution given by Edwin in his post is ONLY PART of the FULL solution, and being the part, only, \r
\n" ); document.write( "\n" ); document.write( "            IT DOES NOT GIVE the full solution.\r
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\n" ); document.write( "\n" ); document.write( "            His solution for the local minimum/maximum should be supplemented by the end-behavior analysis \r
\n" ); document.write( "\n" ); document.write( "            of the function f(x) = x^2 - x.\r
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document.write( "This end-behavior analysis gives the values\r\n" );
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document.write( "    (a)  at x = -2,  f(-2) = (-2)^2 - (-2) = 4 + 2 = 6;\r\n" );
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document.write( "    (a)  at x =  2,  f(2)  =   2^2  -   2  = 4 - 2 = 2.\r\n" );
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document.write( "So, the answer is:  in the interval [-2,2],  the number which provides the maximum of the function f(x) = x^2 - x, is the value of x= -2.\r\n" );
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\n" ); document.write( "\n" ); document.write( "As you see, the correct answer is totally different from that by Edwin.\r
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\n" ); document.write( "\n" ); document.write( " For better understanding, see the plot below.\r
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document.write( "     Plot y =  (red),  y = x (green)  and  the difference y =  (blue)\r\n" );
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