00:01
Okay, so you have a function that is increasing on one to four.
00:06
So here is an increasing function.
00:11
Let's put it on an axis.
00:15
Here is one.
00:19
Here is four.
00:20
And you are dividing it into 12 sub -intervals.
00:24
So remand -sums, these are called remand -sums, they can get a little confusing with the formulas involved, like all the x sub -i's.
00:32
I really recommend don't separate yourself from reality.
00:35
You are finding areas of rectangles, and that is it.
00:39
Areas of rectangles.
00:41
So here you want 12 rectangles.
00:43
Well, if we put it to you here, that's two rectangles.
00:48
Sorry, yeah, 2 .5.
00:53
Let's do it this way.
00:55
So if we did 1, 2, 3, 4, that would be 4.
01:00
So if we want 12, we would have to separate each of these into 4ths...