Period of a function is always a positive integer.
False
A function f :X→Y is said to be a periodic function if there exists a positive real number p such that f(x +p) = f(x), for all x € X. We call this value p as the period of the functions. From the definition, it is clear that p can be any positive real number, not just positive integers. If you are familiar with period of standard functions, you will see that the period of sinx, is an irrational number, not an integer.