And so the area of a circle is pi r squared, so it'd be pi times our radius, which is two squared, but this is a semicircle, so I'm gonna divide by two. It's only half the area of the full circle. So this is going to be four pi over two, which is equal to two pi. All right, let's do another one. So here we have the definite integral from negative two to one of f of x dx. Pause the video and see if you can figure that out. All right, let's do it together.