SOLUTION: Find the solution set for x^4 - 12x^2 + 32 = 0 Can you please help me out? Thanks so much in advance:)

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Question 872287: Find the solution set for x^4 - 12x^2 + 32 = 0
Can you please help me out? Thanks so much in advance:)
Answer by josgarithmetic(39630) About Me  (Show Source):
You can put this solution on YOUR website!
Try a substitution, like u=x^2, and then solve for u. You next must solve for x from reversing the substitution. You may find four different solutions.

%28u-4%29%28u-8%29=0
u=4 OR u=8.

x%5E2=4
x=-2 or x=2;

x%5E2=8
x=-sqrt(2*2*2)=-2*sqrt(2)
or
x=2*sqrt(2)

SUMMARY OF SOLUTION
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x=-2 OR x=2 OR x=-2sqrt%282%29 OR x=2sqrt%282%29
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