document.write( "Question 516281: Please help me solve this equation
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Algebra.Com's Answer #344320 by Edwin McCravy(20059)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "x³ - 4x² + 21x - 34\r\n" );
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document.write( "The possible rational zeros are ± the divisors of \r\n" );
document.write( "34 which are ±1,±2,±17,±34\r\n" );
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document.write( "Try 1\r\n" );
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document.write( "1 |1 -4 21 -34\r\n" );
document.write( "  |   1 -3  18\r\n" );
document.write( "   1 -3 18  16\r\n" );
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document.write( "No, that gives a 16 remainder, not 0.\r\n" );
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document.write( "Try -1\r\n" );
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document.write( "-1 |1 -4 21 -34\r\n" );
document.write( "   |  -1  5 -26\r\n" );
document.write( "    1 -5 26 -60\r\n" );
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document.write( "No, that gives a -60 remainder, not 0.\r\n" );
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document.write( "Try 2\r\n" );
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document.write( "2 |1 -4 21 -34\r\n" );
document.write( "  |   2 -4  34\r\n" );
document.write( "   1 -2 17   0\r\n" );
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document.write( "Yay!  That gives a 0 remainder, so 2 is a zero.\r\n" );
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document.write( "So x = 2 is a solution and that is equivalent\r\n" );
document.write( "to  x - 2 = 0, so x - 2 is a factor, and we have\r\n" );
document.write( "factored the polynomial as\r\n" );
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document.write( "(x - 2)(x² - 2x + 17)\r\n" );
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document.write( "So we set each factor equal to 0:\r\n" );
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document.write( "x - 2 = 0      x² - 2x + 17 = 0\r\n" );
document.write( "    x = 2        doesn't factor.\r\n" );
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document.write( "So we use the quadratic formula:\r\n" );
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document.write( "Compare 1x² - 2x + 17 = 0 to ax² + bx + c = 0\r\n" );
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document.write( "a = 1, b = -2, c = 17\r\n" );
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document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"\r\n" );
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document.write( "\"x+=+%282+%2B-+sqrt%284-68%29%29%2F2+\"\r\n" );
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document.write( "\"x+=+%282+%2B-+sqrt%28-64%29%29%2F2+\"\r\n" );
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document.write( "\"x+=+%282+%2B-+i%2Asqrt%2864%29%29%2F2+\"\r\n" );
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document.write( "\"x+=+%282+%2B-+i%2A8%29%2F2+\"\r\n" );
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document.write( "\"x+=+%282+%2B-+8i%29%2F2+\"\r\n" );
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document.write( "Make two fractions:\r\n" );
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document.write( "\"x+=+2%2F2+%2B-+8i%2F2+\"\r\n" );
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document.write( "\"x+=+1+%2B-+4i\"\r\n" );
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document.write( "Complex zeros: 1 + 4i, 1 - 4i\r\n" );
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document.write( "Edwin
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