f prime of g of x. Well, where everywhere in the derivative we saw an x, we can replace it with a g of x. It's going to be 1 half times, instead of an x to the negative 1 half, we can write a g of x. We can write a g of x to the 1 half. And this is just going to be equal to, let me write it right over here, it's going to be equal to 1 half times all of this business to the negative 1 half power. So 3x squared minus x, which is exactly what we need to solve right over here. f prime of g of x is equal to this.