SOLUTION: find a cubic equation with integra; coefficients that has -3 and 2i as roots

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Question 476437: find a cubic equation with integra; coefficients that has -3 and 2i as roots
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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find a cubic equation with integra; coefficients that has -3 and 2i as roots
:
1st factor: (x+3) = 0
Find the the other factor
x = 2i
x^2 = (2i)^2
x^2 = 4(-1)
x^2 = -4
(x^2 + 4) = 0 is the other factor
:
FOIL (x^2+4)(x+3) = x^3 + 3x^2 + 4x + 12