Just as a review, the chain rule says, look, if we're trying to take the derivative with respect to x of f of g of x, f of g of x, f of g of x, that this is going to be equal to, this is going to be equal to the derivative of the whole thing with respect to g of x. So I could write that as f prime of g of x, f prime of g of x, times the derivative of the inner function with respect to x, times g prime of x. So over here, we could view our f function as a thing that takes its input and takes it to the third power. And so this right over here is f prime of g of x. So this thing is the f prime of g of x, but she forgot to multiply it by the derivative of the inner function with respect to x. So she forgot to multiply this times the derivative of two x squared minus four with respect to x, which is going to be, let's see, the derivative of two x squared, power rule, two times two is four, so it's gonna be four x to the first. And then the derivative of negative four is just zero, so it's just gonna be times four x.