Ok, so
We're going to graph the function y = cos(x).
That is one cycle of the function in the right side.
Now, let's graph the other side.
Finally:
1. The amplitude of the function is 1. Because as you can see, the function oscilates between -1 and 1.
2. The zeros of the function in this side, are:
-3pi/2 , -pi/2, pi/2 and 3pi/2.
3. Its period, is equal to 2pi. That's because it completes an oscillation in 2pi.
