So if y is the inverse sine of x, that's just like saying that, that's equivalent to saying that sine of y is equal to x. Sine of y is equal to x. So now we have things that we're a little bit more familiar with, and now we can do a little bit of implicit differentiation. We could take the derivative of both sides with respect to x. So derivative of the left-hand side with respect to x and the derivative of the right-hand side with respect to x. Well, what's the derivative of the left-hand side with respect to x going to be? And here we just apply the chain rule.