I'd doing a chapter on graphing sine waves, and finding the amplitude, period, and so on.
I know something like $y = 2 \sin(3x+ \pi) + 1$ can be turned into $y = 2 \sin[3(x + \pi/3)] + 1$ following the $y = A \sin[B(x-C)] + D$ format, with amplitude 2, period being $(2\pi)/2$, and a phase shift of $\pi/3$. But what do you do with something like $y = 2 - \sin(x/4)$? I don't have any examples with just $x$ divided by something in the book, other then a problem that just gives an unexplained answer.
Hint: You can express $$y = 2 - \sin\left(\frac{x}{4}\right)$$ in the form $$y = -1\sin\left[\frac{1}{4}(x - 0)\right] + 2$$