Let's get some practice rewriting definite integrals as the limit of a Riemann sum. So let's say I wanted to take the definite integral from pi to two pi of cosine of x dx. And what I want to do is I want to write it as the limit as n approaches infinity of a Riemann sum. So it's gonna take the form of the limit as n approaches infinity, and we can have our sigma notation right over here. And I would say from, let's say, i is equal to one all the way to n. Let me scroll down a little bit so it doesn't get all squenched up at the top. Of, and so let me draw what's actually going on so that we can get a better sense of what to write here within the sigma notation. So, let me do it large.