Answer
$\log_2{3}$
Work Step by Step
Recall the quotient property of logarithms (pg. 462):
$\log_b{\frac{m}{n}}=\log_b{m}-\log_b{n}$
Using the formula in reverse (with $m=9$, $n=3$), we have:
$\log_2 {9}-\log_2{3}=\log_2{\frac{9}{3}}=\log_2{3}$