If I set u to be equal to seven x plus nine, what is the derivative of u with respect to x going to be? Derivative of u with respect to x is just going to be equal to seven. Derivative of seven x is seven, derivative of nine is zero. So do we see a seven lying around anywhere over here? Well, we don't. But what could we do in order to have a seven lying around but not change the value of the integral? Well, the neat thing, and we've seen this multiple times, is when you're evaluating integrals, scalars can go in and outside of the integral very easily.