SOLUTION: 15t^4-34t^2+15=0???

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Question 255903: 15t^4-34t^2+15=0???
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
We are going to solve with a "dummy variable" of U = t^2.
SInce u = t^2, U^2 = t^4. By substitution of our dummy variable, we get
15U%5E2+-+34U+%2B+15+=+0
This looks more familiar and we apply factoring to get
%285U+-3%29%283U-5%29+=+0
Solve each for U to get
5U-3+=+0
U+=+3%2F5
and
3U-5+=+0
U+=+5%2F3
resub t^2 for U to get
t%5E2+=+3%2F5
t+=+sqrt%283%2F5%29
and
t%5E2+=+5%2F3
t+=+sqrt%285%2F3%29