So the problem indicates:

Suppose y= sin x , for x in [n/2, 3n/2] *note let n=pi

Then we define P to be the inverse of this function.

Ex. P(0) = n

a. Obtain the derivative of P. The derivative is not P'(x) = 1/[(1-x^2)^(1/2)].

So I'm not entirely sure how to go about this.

We can write P(x) =y for x in [-1, 1].

Then I know that on the interval [n/2, 3n/2] the derivative of the sine function will be negative.

But I'm unsure how to approach it?