SOLUTION: Find Complex Roots: x^4 -11x^2 +28 =0

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Question 310368: Find Complex Roots:
x^4 -11x^2 +28 =0
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
let y^2=x^4 and y=x^2
y^2-11y+28=0
(y-4)*(y-7)=0
y=4 and y=7
x^2=4
x=+-2
x^2=7
x=+-sqrt(7)
There are no complex roots.