SOLUTION: Find a polynomial f(x) of degree 3 with real coefficients and the following zeros -4,1-i f(x)=

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Question 962437: Find a polynomial f(x) of degree 3 with real coefficients and the following zeros -4,1-i
f(x)=
Answer by hkwu(60) About Me  (Show Source):
You can put this solution on YOUR website!
By the Conjugate Roots Theorem, if f(x) has real coefficients and has a complex root, then the conjugate of that complex root is also a root of f(x). Thus we immediately get
f%28x%29=%28x%2B4%29%28x-%281-i%29%29%28x-%281%2Bi%29%29
f%28x%29=%28x%2B4%29%28x-1%2Bi%29%28x-1-i%29