SOLUTION: N=3; 3 and 4i are zeros; F(2)=-40

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Question 1074491: N=3;
3 and 4i are zeros;
F(2)=-40
Answer by josgarithmetic(39626) About Me  (Show Source):
You can put this solution on YOUR website!
a%28x-3%29%28x-4i%29%28x%2B4i%29=F%28x%29

F%28x%29=a%28x-3%29%28x%5E2-16i%5E2%29

F%28x%29=a%28x-3%29%28x%5E2%2B16%29

-
-40=a%282-3%29%284%2B16%29

-a%2A20=-40
a=2

-
highlight%28F%28x%29=2%28x-3%29%28x%5E2%2B16%29%29
You can fully multiply the right hand side and put in general form if you want.