Answer:
What is the question?
Step-by-step explanation:
The trapezoidal approximation will be the average of the left- and right-endpoint approximations.
Let's consider a simple example of estimating the value of a general definite integral,

Split up the interval
![[a,b]](https://tex.z-dn.net/?f=%5Ba%2Cb%5D)
into

equal subintervals,
![[x_0,x_1]\cup[x_1,x_2]\cup\cdots\cup[x_{n-2},x_{n-1}]\cup[x_{n-1},x_n]](https://tex.z-dn.net/?f=%5Bx_0%2Cx_1%5D%5Ccup%5Bx_1%2Cx_2%5D%5Ccup%5Ccdots%5Ccup%5Bx_%7Bn-2%7D%2Cx_%7Bn-1%7D%5D%5Ccup%5Bx_%7Bn-1%7D%2Cx_n%5D)
where

and

. Each subinterval has measure (width)

.
Now denote the left- and right-endpoint approximations by

and

, respectively. The left-endpoint approximation consists of rectangles whose heights are determined by the left-endpoints of each subinterval. These are

. Meanwhile, the right-endpoint approximation involves rectangles with heights determined by the right endpoints,

.
So, you have


Now let

denote the trapezoidal approximation. The area of each trapezoidal subdivision is given by the product of each subinterval's width and the average of the heights given by the endpoints of each subinterval. That is,

Factoring out

and regrouping the terms, you have

which is equivalent to

and is the average of

and

.
So the trapezoidal approximation for your problem should be
Answer:
21, 23, 25
Step-by-step explanation:
Ok, so this one may seem a little tricky, so I'll try to explain it as best as I can. :)
So because they are consecutive odd numbers, that means they are odd numbers that are one after the other. This means each number is 2 apart from the next. So by using this, we know that there is a difference of 6 between the highest and lowest number. Now let's try and make an equation:
3o + 6 = 69
Now in order to get O by itself we have to subtract 6 from both sides:
3o = 63
Now we just have to divide by three on both sides:
o = 21
So now, we know that the lowest number is 21, but we have to add 2 to get 23, and then another 2 to get 25.
Hope this helps :)