document.write( "Question 334835: Find all the roots of the following polynomial in the complex number system.
\n" ); document.write( "f(x)=x^3-8x^2+36x-80
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Algebra.Com's Answer #239911 by Fombitz(32388)\"\" \"About 
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Graphing the function, \"x=4\" is the only real root.
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\n" ); document.write( "\"graph%28300%2C300%2C-2%2C6%2C-4%2C4%2Cx%5E3-8x%5E2%2B36x-80%29\"
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\n" ); document.write( "Use polynomial long division to find the remaining quadratic equation,
\n" ); document.write( "\"%28x%5E3-8x%5E2%2B36x-80%29%2F%28x-4%29\"
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\n" ); document.write( "First term : \"x%5E2\"
\n" ); document.write( "\"x%5E2%28x-4%29=x%5E3-4x%5E2\"
\n" ); document.write( "Subtract this product from the original polynomial to get the remainder,
\n" ); document.write( "\"%28x%5E3-8x%5E2%2B36x-80%29-%28x%5E3-4x%5E2%29=-4x%5E2%2B36x-80\"
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\n" ); document.write( "Second term : \"-4x\"
\n" ); document.write( "\"-4x%28x-4%29=+-4x%5E2%2B16x\"
\n" ); document.write( "Subtract this product from the remainder to get the new remainder,
\n" ); document.write( "\"%28+-4x%5E2%2B36x-80%29-%28-4x%5E2%2B16x%29=20x-80\".
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\n" ); document.write( "Final term : \"20\"
\n" ); document.write( "\"20%28x-4%29=20x-80\"
\n" ); document.write( "Subtract this product from the remainder to get the new remainder,
\n" ); document.write( "\"%28+20x-80%29-%2820x-80%29=0\".
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\n" ); document.write( "Gather the terms,
\n" ); document.write( "\"%28x%5E3-8x%5E2%2B36x-80%29%2F%28x-4%29=%28x%5E2-4x%2B20%29\"
\n" ); document.write( "Complete the square to get the remaining roots,
\n" ); document.write( "\"x%5E2-4x%2B20=0\"
\n" ); document.write( "\"x%5E2-4x%2B4%2B16=0\"
\n" ); document.write( "\"%28x-2%29%5E2=-16\"
\n" ); document.write( "\"x-2=0+%2B-+4i\"
\n" ); document.write( "\"x=2+%2B-+4i\"
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