Draw the graph of `y=f(x)=sqrt(1-cosx)`

Explanation

We have `y=f(x)=sqrt(1-cosx)`
`=sqrt(2sin^(2))(x)/(2)`
`=sqrt2|sin(x)/(2)|`
Now the period of `y=sin""(x)/(2)` is `4pi`, the graph of which is as shown in the following figure.

Therefore, the graph of `y=|sin""(x)/(2)|` is as follows.
The graph of `y=sqrt2|sin""(x)/(2)|` can be obtained by stretching the above graph `sqrt2` times vertically.