How to put ina sub unit for log

Type this :

log ( a , b)     where a is the number you're taking the log of [ the antilog] and b is the base

For instance....for log₂ 8

log ( 8, 2)   will return "3"

Uh in a calculator I'm not sure, I've always been bad at logarithms haha.

Nevermind listen CPhill :) 

Also if you have a TI 84 or above there is a key under the math button. I believe it's the second from the bottom. If you have below a TI 84, you must use the change of base property.