Free interactive math game: Logarithm Identities — log(1)=0, log_a(a)=1. Part of the Logarithms category on MathKite.
Taken from the generator that powers this exercise. A fresh set appears every time the page is opened, and the printable worksheet holds ten of them.
The two logarithms that hold for every base.
The log of 1 is always 0, and the log of the base itself is always 1.
Log base 7 of 7 is 1, and log base 7 of 1 is 0.
Swapping the two. Any base to the power zero is 1, which is what fixes them.