An Introduction to Periodic Functions
Concept

Amplitude

The amplitude is half the difference of the maximum and minimum values of a periodic function.

To find the amplitude of a periodic function, begin by identifying its maximum and minimum values. Then, determine half the vertical distance between those values.
The amplitude of a periodic function does not depend on the period of the function. Drag the glider in the following applet to change the period of the function.
Additionally, because translations move all the points from a graph in the same way, even if a graph is translated, its amplitude does not change. For functions that are not sine or cosine, there are various alternative definitions of amplitude.

Extra

Peak-to-Peak Amplitude

The peak-to-peak amplitude is defined as the distance between the highest value and the lowest value of a periodic function.

Exercises