document.write( "Question 1003820: What is the sum of the irrational roots of x^4+x^3-5x^2-3x+6=0?
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Algebra.Com's Answer #620448 by Edwin McCravy(20060)\"\" \"About 
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document.write( "\"x%5E4%2Bx%5E3-5x%5E2-3x%2B6=0\"\r\n" );
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document.write( "The potential rational roots are ± the factors of the\r\n" );
document.write( "last term (in absolute value).\r\n" );
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document.write( "±1, ±2, ±3, ±6\r\n" );
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document.write( "We try 1\r\n" );
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document.write( "1 |1  1 -5 -3  6\r\n" );
document.write( "  |   1  2 -3 -6\r\n" );
document.write( "   1  2 -3 -6  0\r\n" );
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document.write( "So we have factored the equation as:\r\n" );
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document.write( "\"%28x-1%29%28x%5E3%2B2x%5E2-3x-6%29=0\"\r\n" );
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document.write( "We can factor the expression in the second parentheses\r\n" );
document.write( "by grouping, ie., factor the first two terms and factor\r\n" );
document.write( "the last two terms:\r\n" );
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document.write( "\"%28x-1%29%28x%5E2%28x%2B2%29-3%28x%2B2%29%29=0\"\r\n" );
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document.write( "Factor (x+2) out of the big parentheses:\r\n" );
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document.write( "\"%28x-1%29%28x%2B2%29%28x%5E2-3%29=0\"\r\n" );
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document.write( "Use zero-factor property:\r\n" );
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document.write( "\"x-1=0\"; \"x%2B2=0\"; \"x%5E2-3=0\"\r\n" );
document.write( "\"x=1\";    \"x=-2\";  \"x%5E2=3\"\r\n" );
document.write( "                   \"x=%22%22+%2B-+sqrt%283%29\"\r\n" );
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document.write( "The irrational roots are \"sqrt%283%29\" and \"-sqrt%283%29\".\r\n" );
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document.write( "Their sum is 0.\r\n" );
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document.write( "Edwin
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