SOLUTION: x^4-9x^2+8=0

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Question 536439: x^4-9x^2+8=0
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
x^4-9x^2+8=0
(x^2-8)(x^2-1)=0
(x^2-8)(x+1)(x-1)=0
x^2-8=0
x^2=8
x=+-sqrt(8)
=+-sqrt(4*2)
x=2sqrt(2), x=-2sqrt(2), x=1, x=-1 Four answers
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Ed