f prime of g of x is equal to this. So this part right over here, I will, let me square it off in green. What we're trying to solve right over here, f prime of g of x, we have just figured out, is exactly this thing right over here. It's the derivative of f of the outer function with respect to the inner function. So let me write it. It is equal to 1 half times g of x to the negative 1 half times 3x squared minus x. This is exactly this, based on how we've defined f of x and how we've defined g of x.