SOLUTION: I need some help with this problem: {{{x^4-4x^2+3}}}.Thanks.

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Question 8436: I need some help with this problem: x%5E4-4x%5E2%2B3.Thanks.
Found 2 solutions by drglass, khwang:
Answer by drglass(89) About Me  (Show Source):
You can put this solution on YOUR website!
This is a little tricky, but you can make it easy on yourself by noticing that this is a quadratic equation is disguise. Let's let y+=+x%5E2 and rewrite the expression as follows:
y%5E2+-+4y+%2B+3,
now factor it:
%28y+-+4%29%28y+-+1%29.
This is not quite the answer, we are looking for x not y, so let's replace x%5E2 for y:
%28x%5E2+-+4%29%28x%5E2+-+1%29

Answer by khwang(438) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E4-4x%5E2%2B3
= %28x%5E2-1%29 %28x%5E2-3%29
= %28x-1%29 %28x%2B1%29 %28x%5E2-3%29
[Or stop here if restriceted to rationals]
= (x-1)(x+1)(x-sqrt(3))(x+sqrt(3)) [in reals]
Forget another wrong solution.
Kenny