So u prime of x, well that's going to be two x to the first, which is just two x, minus one. So we're going to multiply this times two x, two x minus one. So there you have it. That is the derivative of y with respect to x. You could, we could try to simplify this or I guess re-express it in different ways, but the main thing to realize is, look, we're just going to take the derivative of the seven to the, this to the u of x power with respect to u of x. So we treat the u of x the way that we would have treated an x right over here. So it's going to be natural log of seven times seven to the u of x power.