And then we could divide the numerator and the denominator by h. So this simplifies too. So we get f prime of x is equal to, if we divide the numerator and denominator by h, we get 2x plus h. Oh, sorry. I forgot my limit. 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.