SOLUTION: How do i find the polynomial function of these three zeros : 2i, 7, -1

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Question 1008613: How do i find the polynomial function of these three zeros : 2i, 7, -1
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
zeros :
x%5B1%5D=2i,=> then you also have x%5B2%5D=-2i (complex roots always come in pairs)

x%5B3%5D=7,
x%5B4%5D=+-1

f%28x%29=%28x-x%5B1%5D%29%28x-x%5B2%5D%29%28x-x%5B3%5D%29%28x-x%5B4%5D%29

f%28x%29=%28x-2i%29%28x-%28-2i%29%29%28x-7%29%28x-%28-1%29%29

f%28x%29=%28x-2i%29%28x%2B2i%29%28x-7%29%28x%2B1%29

f%28x%29=%28x%5E2-%282i%29%5E2%29%28x-7%29%28x%2B1%29

f%28x%29=%28x%5E2-4i%5E2%29%28x%5E2%2Bx-7x-7%29

f%28x%29=%28x%5E2-4%28-1%29%29%28x%5E2-6x-7%29

f%28x%29=%28x%5E2%2B4%29%28x%5E2-6x-7%29

f%28x%29=x%5E4-6x%5E3-7x%5E2%2B4x%5E2-24x-28

f%28x%29=x%5E4-6x%5E3-3x%5E2-24x-28

+graph%28+600%2C+600%2C+-10%2C+10%2C+-50%2C+50%2C+x%5E4-6x%5E3-3x%5E2-24x-28%29+