Well, the derivative of the natural log of x is one over x. We show that in other videos. And so we now know what u prime of x is. What is, we know what v prime of x is, but what is v prime of u of x? Well, v prime of u of x, wherever we see the x, we replace it, let me write that a little bit neater, we replace that with a u of x. So v prime of u of x is going to be equal to, is going to be equal to one over u of x, one over u of x, u of x, which is equal to, which is equal to one over, u of x is just the square root of x, one over the square root of x. So this thing right over here, we have figured out is one over the square root of x, and this thing, u prime of x, we figured out is 1 1⁄2 times x to the negative 1 1⁄2, and x to the negative 1 1⁄2, I could rewrite that as 1 1⁄2 times one over x to the 1 1⁄2, which is the same thing as 1 1⁄2 times one over the square root of x, or I could write that as one over two square roots of x.