What I want to do in this video is start with the abstract, I guess you could call it formula for the chain rule, and then learn to apply it in the concrete setting. So let's start off with some function, some expression, that can be expressed as the product of two functions, or the composition of two functions. So it can be expressed as f of g of x. So it's a function that can be expressed as a composition or expression that can be expressed as a composition of two functions. Let me get that same color. I want the colors to be accurate. And my goal is to take the derivative of this business, the derivative with respect to x.