So all we've done is we've rewritten this thing in a way that we're used to applying the fundamental theorem of calculus. So if we want to find f prime of x, well, applying the derivative operator over here, we're going to have a negative out front. It's going to be equal to negative cosine x over x. Once again, just the fundamental theorem of calculus. And then plus, we're first going to take the derivative of this thing with respect to x squared. And that's going to give you cosine of x squared over x squared. Wherever you saw a t, you replace it with an x squared.