document.write( "Question 927772: Find the sum of the cubes of the roots of $\"+x%5E2-2x%2B13=0+\"$ , but do not find the roots. \n" ); document.write( "

Algebra.Com's Answer #563228 by Edwin McCravy(20055) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "The other tutor did EXACTLY what you were told NOT to do!!!!\r\n" );
document.write( "She found the roots!!!  She got an approximate version of the\r\n" );
document.write( "answer, but the answer oames out exactly as an integer.\r\n" );
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document.write( "Here's how to do it as you were told to do it.\r\n" );
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document.write( "A \"monic\" polynomial is a polynomial whose leading coefficient is 1.\r\n" );
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document.write( "The coefficient of the next to largest power of x in a monic polynomial is\r\n" );
document.write( "-1 times the sum of the roots.\r\n" );
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document.write( "The last term of a monic polynomial in x is the product of the roots if the\r\n" );
document.write( "degree is even [and -1 times the product of the roots if the degree is odd.]\r\n" );
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document.write( " is a monic polynomial of even degree 2.\r\n" );
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document.write( "Therefore the sum of its roots is 2 and the product of its roots is 13.\r\n" );
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document.write( "Let its roots be  and \r\n" );
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document.write( "Then  and \r\n" );
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document.write( "So\r\n" );
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document.write( "Substitute:  and \r\n" );
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document.write( "Edwin

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