document.write( "Question 270279: Given P(x)= x^4-2x^3+7x^2-18x-18 \r
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\n" ); document.write( "\n" ); document.write( "A)show that -3i is a root of P(x)
\n" ); document.write( "B)Factor P(x) into linear factors \n" ); document.write( "

Algebra.Com's Answer #198023 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!
Hints:\r
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\n" ); document.write( "\n" ); document.write( "A) Simply plug in $\"x=-3i\"$ and show that doing so will result in 0. In other words, show that $\"P%28-3i%29=0\"$ \r
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\n" ); document.write( "\n" ); document.write( "B) Since -3i is a root, 3i is also a root. This means that $\"x%5E2%2B9\"$ is a factor. Now use $\"x%5E2%2B9\"$ to factor $\"x%5E4-2x%5E3%2B7x%5E2-18x-18+\"$ (use polynomial long division) into two quadratics. Factor the resulting quadratic further if possible. \n" ); document.write( "

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