document.write( "Question 379728: I asked about this yesterday. I managed to divide the following polynomial and come up with an answer. I need someone to show me how to \"check\" it.\r
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\n" ); document.write( "Comes up with this answer (3 x^2-3 x+2)/(x+1)
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Algebra.Com's Answer #269636 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "(x³ + 2x² - 3x + 2) ÷ (x + 1)\r\n" );
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document.write( "You need to review how to do long division.\r\n" );
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document.write( "            x² +  x - 4 + \r\n" );
document.write( "x + 1)x³ + 2x² - 3x + 2  \r\n" );
document.write( "      x³ +  x²\r\n" );
document.write( "            x² - 3x\r\n" );
document.write( "            x² +  x\r\n" );
document.write( "                -4x + 2\r\n" );
document.write( "                -4x - 4\r\n" );
document.write( "                      6\r\n" );
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document.write( "Answer: x² + x - 4 +  \r\n" );
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document.write( "To check:  Substitute 1 and 0 in original and in answer\r\n" );
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document.write( "Substitute 1 in the original:\r\n" );
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document.write( "(x³ + 2x² - 3x + 2) ÷ (x + 1)\r\n" );
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document.write( "((1)³ + 2(1)² - 3(1) + 2) ÷ ((1) + 1)\r\n" );
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document.write( "((1) + 2(1) - 3(1) + 2) ÷ ((1) + 1)\r\n" );
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document.write( "(1 + 2 - 3 + 2) ÷ (1 + 1)\r\n" );
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document.write( "              2 ÷ 2\r\n" );
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document.write( "                1\r\n" );
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document.write( "----------------------------------\r\n" );
document.write( "Substitute 1 in answer:\r\n" );
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document.write( "x² + x - 4 + \r\n" );
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document.write( "(1)² + (1) - 4 + \r\n" );
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document.write( "1 + 1 - 4 + \r\n" );
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document.write( "-2 + \r\n" );
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document.write( "-2 + 3\r\n" );
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document.write( "  1\r\n" );
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document.write( "Substitute 0 in the original:\r\n" );
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document.write( "(x³ + 2x² - 3x + 2) ÷ (x + 1)\r\n" );
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document.write( "((0)³ + 2(0)² - 3(0) + 2) ÷ ((0) + 1)\r\n" );
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document.write( "((0) + 2(0) - 0 + 2) ÷ ((0) + 1)\r\n" );
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document.write( "(0 + 0 - 0 + 2) ÷ (0 + 1)\r\n" );
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document.write( "              2 ÷ 1\r\n" );
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document.write( "                2\r\n" );
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document.write( "----------------------------------\r\n" );
document.write( "Substitute 0 in answer:\r\n" );
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document.write( "x² + x - 4 + \r\n" );
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document.write( "(0)² + (0) - 4 + \r\n" );
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document.write( "0 + 0 - 4 + \r\n" );
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document.write( "-4 + \r\n" );
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document.write( "-4 + 6\r\n" );
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document.write( "   2\r\n" );
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document.write( "---------------\r\n" );
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document.write( "So we get 1 when we substitute 1 in both the original\r\n" );
document.write( "and the answer, and we get 2 when we substitute 0 in\r\n" );
document.write( "both the original and the answer, so that shows that\r\n" );
document.write( "this is very likely the correct answer.\r\n" );
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document.write( "Edwin

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