SOLUTION: degree if 3 zeros: 1+i and -5........form a polynomial f(x) with real coefficients have the given degree and zeros

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Question 378947: degree if 3 zeros: 1+i and -5........form a polynomial f(x) with real coefficients have the given degree and zeros
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Complex roots always come in complex conjugate pairs.
Since x=1%2Bi is a solution, x=1-i is also a solution.
f%28x%29=%28x%2B5%29%28x-%281%2Bi%29%29%28x-%281-i%29%29
f%28x%29=%28x%2B5%29%28x%5E2-2x%2B2%29
f%28x%29=%28x%5E3-2x%5E2%2B2x%29%2B%285x%5E2-10x%2B10%29
f%28x%29=x%5E3%2B3x%5E2-8x%2B10