That is the equation of the tangent line. Now part b, find the area of r. So r is this region right over here. It's bounded above by g of x, which they've defined as sine of pi x. It's bounded below by f of x, or 8x to the third. So the area is going to be, actually let me just do it, I'll scroll down a little bit. I still want to be able to see this graph right over here. Part b, the area of r is going to be equal to the integral from 0, that's this point of intersection right over here, to 1 half.