Answer
(a) reflect $f(x)$ about the y-axis.
(b) stretch $f(x)$ vertically by a factor of 3
Work Step by Step
(a) We can obtain $f(-x)$ by reflecting the graph of $f(x)$ about the $y$-axis.
(b) We can obtain $3f(x)$ by stretching the graph of $f(x)$ vertically by a factor of 3.
