document.write( "Question 140325: Given that \"1%2B2i\" and \"1-2i\" are zeros of \"x%5E4-4x%5E3%2B6x%5E2-4x-15\", find the other zeros\r
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Algebra.Com's Answer #102191 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"x=1%2B2i\" or \"x=1-2i\" Start with the given zeros\r
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\n" ); document.write( "\n" ); document.write( "\"x-1=2i\" or \"x-1=-2i\" Subtract 1 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-1%29%5E2=4i%5E2\" or \"%28x-1%29%5E2=4i%5E2\" Square both sides\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-1%29%5E2=4%28-1%29\" or \"%28x-1%29%5E2=4%28-1%29\" Replace \"i%5E2\" with -1\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-1%29%5E2=-4\" or \"%28x-1%29%5E2=-4\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-1%29%5E2%2B4=0\" or \"%28x-1%29%5E2%2B4=0\" Add 4 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-2x%2B5=0\" or \"x%5E2-2x%2B5=0\" Foil and simplify\r
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\n" ); document.write( "\n" ); document.write( "Now since \"x%5E2-2x%2B5\" is a factor of \"x%5E4-4x%5E3%2B6x%5E2-4x-15\", we can use long division to find another factor\r
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\n" ); document.write( "\n" ); document.write( "\"Photobucket\"\r
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\n" ); document.write( "\n" ); document.write( "So another factor of \"x%5E4-4x%5E3%2B6x%5E2-4x-15\" is \"x%5E2-2x-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-2x-3=0\" Set the factor equal to zero\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-3%29%28x%2B1%29=0\" Factor the left side (note: if you need help with factoring, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "Now set each factor equal to zero:\r
\n" ); document.write( "\n" ); document.write( "\"x-3=0\" or \"x%2B1=0\" \r
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\n" ); document.write( "\n" ); document.write( "\"x=3\" or \"x=-1\" Now solve for x in each case\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the other zeros are \r
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\n" ); document.write( "\n" ); document.write( " \"x=3\" or \"x=-1\"
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