And if we do that, we'll get a shape that looks like this. I drew it ahead of time just so I could draw it nicely. And as you can see, it looks like some type of a, I don't know, a vase with a hole at the bottom. And so what we're going to do is attempt to do this using, I guess you could call it the washer method, which is a variant of the disk method. So let's construct a washer. So let's look at a given x. So let's say an x right over here.