SOLUTION: log sub2^(9t+5)-log sub2^(t^2-1)=2 any help would be greatly appreciated!!!

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Question 256153: log sub2^(9t+5)-log sub2^(t^2-1)=2
any help would be greatly appreciated!!!
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
I think you mean:
(i) log_2%289t%2B5%29-log_2%28t%5E2-1%29=2
step 1 - rewrite using rules to become
(ii) log_2%28%289t%2B5%29%2F%28t%5E2-1%29%29=2
rewriting as exponents, we get
(iii) 2%5E2+=+%28%289t%2B5%29%2F%28t%5E2-1%29%29
cross multiplying, we get
(iv) 4t%5E2+-+4+=+9t%2B5
setting = 0, we get
(v) 4t%5E2+-+9t+-+9+=+0+
by the quadratic, we get
t = 3 or t = -.75, however we can't use -.75 due to restriction in t^2-1 <0