document.write( "Question 1044048: The curve y=ax^3+2x^2+a^2x+b has a minimum point at (-1,0). Find a and b. \n" ); document.write( "
Algebra.Com's Answer #659284 by josgarithmetic(39616)\"\" \"About 
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\"dy%2Fdx=3ax%5E2%2B4x%2Ba%5E2=0\"----Must be for \"x=-1\".\r
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\n" ); document.write( "\n" ); document.write( "Let x=-1;
\n" ); document.write( "\"3a-4%2Ba%5E2=0\", from the derivative being 0 when x is -1;\r
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\n" ); document.write( "\n" ); document.write( "ALSO from the original equation,
\n" ); document.write( "\"-a%2B2-a%5E2%2Bb=0\"
\n" ); document.write( "so the problem gives the system of equations,\r
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\n" ); document.write( "\n" ); document.write( "\"system%28a%5E2%2B3a-4=0%2Ca%5E2%2Ba-2-b=0%29\"
\n" ); document.write( "Solve this system (first, for \"a\", and then for b).\r
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\n" ); document.write( "First equation of the system is factorable.
\n" ); document.write( "\"%28a-4%29%28a%2B1%29=0\"
\n" ); document.write( "\"system%28a=-1%2Cor%2Ca=4%29\"
\n" ); document.write( "and the description gave, \",... has a minimum point at (-1,0)\".\r
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\n" ); document.write( "\n" ); document.write( "Either the equation becomes \"y=-x%5E3%2B2x%5E2%2Bx%2Bb\" or \"y=4x%5E3%2B2x%5E2%2B16x%2Bb\". Do you believe that the second-derivative might give further information about x at -1 being minimum or maximum?
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