It looks like you have a dx squared. Once again, you're not multiplying them, you're just applying the operator twice. But that's where that notation actually comes from. Well, let's first take the first derivative of y with respect to x. And to do that, let's just remind ourselves that we just have to apply the power rule here. And we can just remind ourselves, based on the fact that y is equal to six x to the negative two. So let's take the derivative of both sides of this with respect to x.