Question

What is the frequency of the sinusoidal graph?

Answer 1

The frequency
`f` is defined as

`f = (1)/(T)`

where
`T` is the period, i.e. the time between two maximum/minimum points.

In your example, you can see that a maximum is reached when
`x = 0`, and the next one at
`x = \pi`. This means that the period is

`T = \pi-0 = \pi`

So, the frequency is

`f = (1)/(\pi)`