(a) Use the horizontal line test to determine whether the function is one-to-one. (b) If the function is one-to-one, then graph the inverse of the function. (Remember that if $f$ is one-to-one and $(a, b)$ is on the graph of $f,$ then $(b, a)$ is on the graph of $f^{-1} .$)
(Check your book for graph)