document.write( "Question 709832: write a polynomial function with rational coefficients so that it has roots (-2, 1+3i ) \n" ); document.write( "
Algebra.Com's Answer #436799 by josgarithmetic(39630)\"\" \"About 
You can put this solution on YOUR website!
You seem to be asking for polynomial function with roots: -2,and 1+3i, AND 1-3i. Complex roots come as conjugate pairs.\r
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\n" ); document.write( "\n" ); document.write( "-2 is a root:
\n" ); document.write( "((-2)-(k))=0
\n" ); document.write( "-2-k=0
\n" ); document.write( "-k=2
\n" ); document.write( "k=-2
\n" ); document.write( "The binomial factor is (x-(-2))=\"%28x%2B2%29\"\r
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\n" ); document.write( "\n" ); document.write( "1+3i is a root:
\n" ); document.write( "(1+3i-k)=0
\n" ); document.write( "1+3i-k=0
\n" ); document.write( "-k=-1-3i
\n" ); document.write( "The binomial factor is (x-(-1-3i))
\n" ); document.write( "or equal to\"+%28x%2B%281%2B3i%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "1-3i is a root:
\n" ); document.write( "(1-3i-k)=0
\n" ); document.write( "-k=-1+3i
\n" ); document.write( "k=1-3i
\n" ); document.write( "The binomial factor is \"%28x-%281-3i%29%29\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "A satisfying function can come from \"%28x%2B2%29%28x%2B%281%2B3i%29%29%28x-%281-3i%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Do the multiplications, at least for the factors containing the complex numbers:
\n" ); document.write( "... The finished polynomial function may be:
\n" ); document.write( "\"highlight%28f%28x%29=%28x%2B2%29%28x%5E2-2x%2B10%29%29\" and you could do the rest of the multiplying if needed.
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