It equals the limit. Very important. Limit as h approaches 0, divide everything by h, and you get 2x plus h squared divided by h is h. If you remember the last video when we did it with a particular x, when we said x is equal to 3, we got 6 plus delta x here, or 6 plus h here. So it's very similar. So if you take the limit as h approaches 0 here, that's just going to disappear. So this is just going to be equal to 2x. So we just figured out that if f of x, this is a big result, this is exciting, that if f of x is equal to x squared, f prime of x is equal to 2x.