## College Algebra (6th Edition)

The graph of $f(x)=4^{x}$ passes through (0,1) and (1,4) ($4^{0}=1$ and $4^{1}=4).$ This graph is not $f(x)=4^{x}$. This graph passes through (0,1) and ($-1,4$), which are reflections of the above points about the y-axis. A reflection about the y-axis of the function $f(x)$ is $f(-x)$. So this function is $f(-x)=4^{-x}=g(x)$