**Definition: **a Function is called periodic with period if for any of the identifying numbers and also included in the scope and

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## Properties of periodic functions

- If the number is a period function , then the number is also the period of the function.
- If the function is periodic with a period , the function is also periodic and its period is
- If the function is periodic with period , then the composed function (function of function) is also periodic with period .
- To plot periodic functions with the period enough to graph on the interval length , and then in parallel to shift this graph along the axis at a distance left and right.