## Precalculus (6th Edition) Blitzer

$(0, +\infty)$; $(-\infty, +\infty)$
RECALL: $y=\log_b{x} \longleftrightarrow b^y=x$, where $x \gt 0$, $b\gt 0$, and $b\ne 1$. Since $x \gt 0$, the domain of the logarithmic function is $(0, +\infty)$. There are no restrictions on $y$, so the range is the set of all real numbers, or $(-\infty, +\infty)$. Thus, the domain of the given function is $(0, +\infty)$, and the range is $(-\infty, +\infty)$.