F.TF.5 Choose trigonometric functions to model periodic phenomena with specified amplitude, frequency, and midline.
Recall that for any function f, you can graph f(x - h) by translating the graph of f by h units horizontally. You can graph f(x) + k by translating the graph of f by k units vertically.
Each horizontal translation of certain periodic functions is a phase shift.
g(x): horizontal translation of f(x)
h(x): vertical translation of f(x). h(x) = f(x) + k
Translations To refresh your memory on translation, go ahead and click on the link.