SOLUTION: n=3 i and 2i are zeros f(-1)=-30

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Question 958161: n=3 i and 2i are zeros f(-1)=-30
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
I'm assuming n is the degree of the polynomial you're seeking(?).
y=%28x-i%29%28x-2i%29%28x-a%29
where a is an unknown to solve.
-30=%28-1-i%29%28-1-2i%29%28-1-a%29
-30=%281%2B2i%2Bi%2B2i%5E2%29%28-1-a%29
-30=%28-1%2B3i%29%28-1-a%29
-1-a=-30%2F%28-1%2B3i%29
-1-a=%28-30%2F%28-1%2B3i%29%29%28%28-1-3i%29%2F%28-1-3i%29%29
-1-a=%2830%2B90i%29%2F%281%2B3i-3i-9i%5E2%29
-1-a=%2830%2B90i%29%2F%281%2B9%29
-1-a=%2830%2B90i%29%2F10
-1-a=3%2B9i
a=-4-9i
So then,
y=%28x-i%29%28x-2i%29%28x-%28-4-9i%29%29
highlight%28y=%28x-i%29%28x-2i%29%28x%2B4%2B9i%29%29