Answer:
[tex]\boxed{f=\dfrac{3}{2\pi}}.[/tex]
Step-by-step explanation:
Notice that the wave completes 3 oscillations at [tex]x=2\pi[/tex]. This means that the period is:
[tex]T = \dfrac{2\pi}{3}.[/tex]
Since the frequency is the reciprocal of the period, we get:
[tex]f= \dfrac{1}{T} = \dfrac{1}{2\pi/3} = \dfrac{3}{2\pi}.[/tex]
So the frequency is:
[tex]\boxed{f=\dfrac{3}{2\pi}}.[/tex]
