For this case what you should see is when the value "y" of any point of the graph is repeated again.
In this case we have that the period will be given by:
T = ((3/4) pi) - ((- 1/4) pi)
T = ((3/4) pi) + ((1/4) pi)
T = ((3 + 1/4) pi)
T = ((4/4) pi)
T = pi
Answer:
the period of the function f(x) shown in the graph is
T = pi
