Log math question....???? help?

Evaluate:
log3 1/81

It says log with a 3 below ......with 1 over 81

Amanda2008-05-27T16:31:44Z

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all this is asking is:

3 to the power of a number is equal to 1/81.

to solve this on your calculator, all you do is log1/81 divided by log 3

this gives you -4.

therefore 3^-4 is 1/81!

Maggie C2008-05-27T16:35:45Z

The log is asking "3 to what power is 1/81?"

3^4 = 81 and we use a negative exponent to invert, so the answer is -4 instead of 4.

Como2008-05-30T04:00:24Z

Let log represent log to base 3.
log (1 / 81) = log (1 / 3^4) = log (3^(-4)) = - 4 log 3 = - 4

Jenova2008-05-27T16:32:19Z

It's -4.

Let me show you why:

1/81 is the same thing as 1 / (3^4) right?
Now we just get rid of the fraction bar by making the power negative. So 1 / (3^4) is now 3^-4

There you go, the answer is -4

Anonymous2008-05-27T16:30:08Z

243/81

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