SOLUTION: evaluate: log9 (81) is the answer 2? or im not sure if there is a definite answer. thanks for your help!

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Question 484848: evaluate:

log9 (81)
is the answer 2?
or im not sure if there is a definite answer.
thanks for your help!
Found 2 solutions by nerdybill, Alan3354:
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
Yes, you're right.
.
log9 (81)
log9 (9^2)
2

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
The log is the exponent.
If you recognize that 81 = 9^2, then
log%289%2C81%29+=+2
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If you don't recognize that, or if it's some other number, eg log%289%2C80%29,
use the base change formula
--------------
log%289%2C81%29+=+log%2881%29%2Flog%289%29