When they look at this, they might see this as being the same as the derivative with respect to x of natural log of x, natural log of x times sine of x. And you can see just the way that it's written, they look very similar. But this is the product of two functions. If you said natural log of x is f of x and sine of x is g of x, this is the product of sine and g of x. This is the product of f of x and g of x. And here you would use the product rule. So to actually compute this, you would use the product, the product rule.