Answer:
The function increase between 0 and 1, and from 2 to infinity.
Explanation:
Any one variable function f(x) increases when f(x2) is greater than f(x1), where x2 is greater than x1. For example, in the plot it can be seen that for x2 = 1, f(x2) = 1 and for x1 = 0, f(x1) = 0. So, between points 0 and 1, the function increase. Also, from 2 onwards, the function increase their values.