## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

$0$
The logarithm of 1 to any valid base is zero. Hence, the given expression, $\log_9 1 ,$ is equal to $0 .$ We can check that this is true: $9^?=1$ $9^0=1$ Because $9^0=1$, the answer that we found above is correct.