SOLUTION: 4x^4-18x^2=0

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Question 10773: 4x^4-18x^2=0
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
4x%5E4+-+18x%5E2+=+0

Factor the common factor first, which is 2x%5E2
2x%5E2%28+2x%5E2+-+9%29+=+0+

Two separate solutions:

First:
2x%5E2+=+0
x%5E2+=+0 so x=0

Second:
2x%5E2+-+9+=+0
2x%5E2+=+9
x%5E2+=+9%2F2

Take square root of both sides:
x+=+sqrt%289%2F2%29 or x+=+-sqrt%289%2F2%29+
x+=+3%2F%28sqrt%282%29%29 or x=+-3%2F%28sqrt%282%29%29+

Another possible way to write the last answers is this:
x+=+%283%2Asqrt%282%29%29%2F2 or x=+%28-3%2Asqrt%282%29%29%2F2

R^2 at SCC