document.write( "Question 975247: n=4; i and 2i are zeros; f(-1)=20
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Algebra.Com's Answer #597085 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
I'm assuming you need real coefficients so you use complex conjugate roots.
\n" ); document.write( " $\"y=a%28x-i%29%28x%2Bi%29%28x-2i%29%28x%2B2i%29\"$
\n" ); document.write( " $\"y=a%28x%5E2%2B1%29%28x%5E2%2B4%29\"$
\n" ); document.write( " $\"y=a%28x%5E4%2B4x%5E2%2Bx%5E2%2B4%29\"$
\n" ); document.write( " $\"y=a%28x%5E4%2B5x%5E2%2B4%29\"$
\n" ); document.write( "When $\"x=-1\"$ , $\"y=20\"$
\n" ); document.write( " $\"20=a%28%28-1%29%5E4%2B5%28-1%29%5E2%2B4%29\"$
\n" ); document.write( " $\"20=a%281%2B5%2B4%29\"$
\n" ); document.write( " $\"20=a%2810%29\"$
\n" ); document.write( " $\"a=2\"$
\n" ); document.write( "So,
\n" ); document.write( " $\"highlight%28y=2x%5E4%2B10x%5E2%2B8%29\"$ \r
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