#### Answer

$log_2{8}=3$

#### Work Step by Step

From the definition of the logarithmic function on page 456, we know that $b^{y}=x$ is equivalent to $y=log_b{x}$ (for $x\gt0$, $b\gt0$, and $b\ne1$).
Therefore, $2^{3}=8$ is equivalent to $log_2{8}=3$ in logarithmic form.