Remember, this thing in the parentheses is a function of x. It's value. It's going to have a value that is dependent on x. You give it a different x, it's going to have a different value. So what's the derivative of this with respect to x? Well, the fundamental theorem of calculus tells us it can be very simple. We essentially, and you can even pattern match up here, and we'll get more intuition of why this is true in future videos.