Answer
$y = 3~sec~\frac{1}{4}x$
We can see the graph below.
Work Step by Step
$y = 3~sec~\frac{1}{4}x$
When $x = -2\pi$, then $y = 3~sec~\frac{-\pi}{2}$ (which is undefined)
When $x = 0$, then $y = 3~sec~0 = 3$
When $x = 2\pi$, then $y = 3~sec~\frac{\pi}{2}$ (which is undefined)
When $x = 4\pi$, then $y = 3~sec~\pi = -3$
When $x = 6\pi$, then $y = 3~sec~\frac{3\pi}{2}$ (which is undefined)
We can see the graph below.
