This is exactly this, based on how we've defined f of x and how we've defined g of x. Conceptually, if you're just looking at this, the derivative of the outer thing, you're taking something to the 1 half power. So the derivative of that whole thing with respect to your something is going to be 1 half times that something to the negative 1 half power. That's essentially what we're saying. But now we have to take the derivative of our something with respect to x. The derivative of our something with respect to x. And that's more straightforward.