SOLUTION: How do I go about solving this equation x^4 – 3x^2 + 2 = 0 when I can't use the formula ax^2+bx+c=0 because the degree is 4?

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Question 122023: How do I go about solving this equation x^4 – 3x^2 + 2 = 0 when I can't use the formula ax^2+bx+c=0 because the degree is 4?
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Try this:
Replace x%5E2 with y.
x%5E4-3x%5E2%2B2+=+0 becomes:
y%5E2-3y%2B2+=+0 Solve by factoring:
%28y-1%29%28y-2%29+=+0 Apply the zero product principle:
y-1+=+0 or y-2+=+0 so then...
y+=+1 or y+=+2
Now replace the y with x%5E2
x%5E2+=+1 or x%5E2+=+2 Take the square root of these:
x+=+1, x+=+-1, x+=+sqrt%282%29, x+=+-sqrt%282%29