SOLUTION: I have never tried one like this can someone help me. the equation is 15x^4-13x^2+2=0

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Question 192032: I have never tried one like this can someone help me. the equation is 15x^4-13x^2+2=0
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for x:
15x%5E4-13x%5E2%2B2+=+0 Temporarily, let y+=+x%5E2 so that y%5E2+=+x%5E4. Make these substitutions.
15y%5E2-13y%2B2+=+0 Factor.
%283y-2%29%285y-1%29+=+0 Apply the zero product rule.
3y-2+=+0 or 5y-1+=+0
3y-2+=+0 Add 2 to both sides.
3y+=+2 Divide both sides by 3.
1) y+=+2%2F3
5y-1+=+0 Add 1 to both sides.
5y+=+1 Divide both sides by 5.
2) y+=+1%2F5
Now substitute back y+=+x%5E2 in both solutions.
x%5E2+=+2%2F3 and x%5E2+=+1%2F5 Take the square root in both cases.
x+=+0%2B-sqrt%282%2F3%29 and x+=+0%2B-sqrt%281%2F5%29
The four solutions are:
x+=+sqrt%282%2F3%29
x+=+-sqrt%282%2F3%29
x+=+sqrt%281%2F5%29
x+=+-sqrt%281%2F5%29