SOLUTION: Find a third-degree polynomial equation with rational coefficients that has the given numbers as roots. 3 + i and -3

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Question 804504: Find a third-degree polynomial equation with rational coefficients that has the given numbers as roots. 3 + i and -3
Answer by erica65404(394) About Me  (Show Source):
You can put this solution on YOUR website!
imaginary roots come in pairs. 3+i, 3-i, -3
(x-(3+i))(x-(3-i))(x+3)
%28x-%283%2Bi%29%29%28x-%283-i%29%29
%28x-3-i%29%28x-3%2Bi%29
x%5E2-3x%2Bix-3x%2B9-3i-ix%2B3i-i%5E2
Combine like terms
x%5E2%2B%28-3x%29%2B%28ix%29%2B%28-3x%29%2B9%2B%28-3i%29%2B%28-ix%29%2B%283i%29-i%5E2
x%5E2-6x%2B10