Now let's take the derivative of both sides with respect to x. On the left-hand side, you're just going to have a one. We're just going to have a one. And on the right-hand side, you're going to have the derivative of cosine y with respect to y, which is negative sine of y times the derivative of y with respect to x, which is dy dx. And so we get, let's see, if we divide both sides by negative sine of y, we get dy dx is equal to negative one over sine of y. Now, like we've seen before, this is kind of satisfying, but we have our derivative in terms of y. We want it in terms of x.