To the second power. Notice, we're just, one way to think about it, is taking the derivative of this outside function with respect to the inside. So I would do the same thing as taking the derivative of x to the third power, but instead of an x, I have a cosine of x. So instead of it being three x squared, it is three cosine of x squared. And then the chain rule says, if we want to finally get the derivative with respect to x, we then take the derivative of cosine of x with respect to x. Now that's a big mouthful, but we are at the home stretch. We've now figured out the derivative.