So let's think about what the derivative of e to the cosine of x is. E to the cosine of x. So we could view our outer function as e to the something, as e to the something. And the derivative of e to the something with respect to something is just going to be e to that something. So it's going to be e to the cosine of x. So let me do that in that same blue color. So it's going to be e, actually let me do it in a new color.