SOLUTION: Please help me in solving this problem Q) Solve for x log(x+1)+log(x-1)=log 8

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Question 393005: Please help me in solving this problem
Q) Solve for x
log(x+1)+log(x-1)=log 8

Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
log(x+1)+log(x-1)=log 8
==> log((x+1)(x-1)) = log 8
==> log%28%28x%5E2+-+1%29%29+=+log+8
==> x%5E2+-+1+=+8, since the log function is one-to-one
<==> x%5E2+-+9+=+0, or (x-3)(x+3) = 0, or x = -3, 3. Since -3 will not satisfy the original equation, the final answer is x =3.