And you could manipulate this in different ways if you like, but the key is to just recognize that this is an application of the chain rule. Derivative of the outside, well, actually, the first thing to realize is the fourth root is the same thing as taking something to the 1 4th power, basic exponent property. And then realize that, okay, I have a composite function here. So I can take the derivative of the outside with respect to the inside, that's what we did here, times the derivative of the inside with respect to x. And so if someone were to tell you, if someone were to say, all right, f of x, f of x is equal to the fourth root of x to the third plus four x squared plus seven. And then they said, well, what is f prime of, I don't know, negative three? Well, you would evaluate this at negative three.