00:01
So for this problem here, they're asking us to use the midpoint ream and sum formula.
00:07
And in order to do that, we first have to establish, well, so what's the intervals? so intervals from 5 to 15, so that's good.
00:16
So that's going to be our a and b here.
00:21
And then we want it in 5 equal rectangles.
00:24
All right, so the formula to find what the change in x would be is equal to b minus a over n so we get 15 minus 5 over 5 that's 10 over 5 which is equivalent to 2 so from there we have that the midpoint formula right is equal to so it's going to be the halfway marks between each of these rectangles that are created because the distance between each x value is going to be 2 that actually makes it very simple because here i'll just lay out what it's going to be in between right so it's going to be 5 to 7 then 7 to 9 to 11 11 to 13 and then 13 to 15.
01:02
And that will give us the five rectangles that we want from here.
01:08
Because we want the midpoint of them, right, we're actually going to take the x values that are in between each of these boundaries that we have here.
01:18
So that gives us to what our sum formula is going to be, and in which case it's just going to be, right, the sum of.
01:26
So this is going to be delta x times.
01:28
And we have f of...