Simply periodic functions

A simply periodic function is characterized by its amplitude, period, and phase shift. The radian frequency is determined then by the formula

frequency = 2 Pi / period

The formula for the function is

f(t) = (amplitude) cos (2 Pi t /period - phaseshift)

The following figure starts with

frequency = 1
period = 2 Pi
amplitude = 1
phase shift a half cycle

Move the nodes to change these quantities.