Make Math Work
Logs

Usage: Log [e | x] [base, ] Number

The Log command will calculate the logarithm of Number to the optional base. If the base is not given it is assumed to be 10. Therefore Log 100 to the base 10 is entered as Log 10.

For bases other than 10 there a two choices:
1) You can use a base of e (the constant 2.71828...) using the syntax Log e Number.
For example, to compute log 12 to the base e, enter Log e 12.

2) You can use any other base by using the syntax Log x Base, Number where Base can be any number.
For example, to compute log 12 to the base 2, enter Log x 2, 12.

Note that Log x 10, 100 would compute the same result as Log 100.

A logarithm to base b of a number x is an exponent that satisfies x = by. It is written logb(x) or, if the base is implicit, log(x). So, a logarithm in essence is the inverse of an exponentiation. y = logb(x) is equivalent to x = by.

Examples:
Log 10
Log e 12
Log x 2, 12