Answer: V =
Explanation:
In the given system of coordinates OXY, the region R₃ is bounded by two functions:
y₁ =
(green line)
y₂ = 2x (blu line)
in the intervals:
0 ≤ x ≤ 1
0 ≤ y ≤ 2
We need to find the volume of this region rotated about the line AB, which is x = 1. In order to do so, we need to change system of coordinates, such as the rotation is about the y-axis, therefore we need to perform a translation:

After the translation R₃ will be bounded by:
y₁ =
y₂ = 2x + 2
in the intervals:
-1 ≤ x ≤ 0
0 ≤ y ≤ 2
At this point, we can use the washer method (see picture attached). The general formula is:
A = π(R² - r²)
where:
A = area
R = outer radius of a washer
r = inner radius of a washer
Since the radii are x-values which vary with the height, represented by the y-values, we need to write the inverse functions:

[Note: I used the curves on the left side of the graph, but you could find the ones representing the right side of the graph and use those]
Now, we can find the function for the area of each washer:
![A(y) = \pi [(\frac{1}{16}y^{4} - 1)^{2} - (\frac{1}{2}y - 1)^{2} ] \\ = \pi [\frac{1}{256}y^{8} - \frac{1}{8} y^{4} - \frac{1}{4} y^{2} + y ]](https://tex.z-dn.net/?f=A%28y%29%20%3D%20%5Cpi%20%5B%28%5Cfrac%7B1%7D%7B16%7Dy%5E%7B4%7D%20-%201%29%5E%7B2%7D%20-%20%28%5Cfrac%7B1%7D%7B2%7Dy%20-%201%29%5E%7B2%7D%20%5D%20%5C%5C%20%3D%20%5Cpi%20%5B%5Cfrac%7B1%7D%7B256%7Dy%5E%7B8%7D%20-%20%5Cfrac%7B1%7D%7B8%7D%20y%5E%7B4%7D%20-%20%5Cfrac%7B1%7D%7B4%7D%20y%5E%7B2%7D%20%2B%20y%20%5D)
Therefore the volume of the region R₃ will be:

![= \int\limits^2_0 {\pi [\frac{1}{256}y^{8} - \frac{1}{8}y^{4} - \frac{1}{4} y^{2} + y] } \, dy](https://tex.z-dn.net/?f=%20%3D%20%5Cint%5Climits%5E2_0%20%7B%5Cpi%20%5B%5Cfrac%7B1%7D%7B256%7Dy%5E%7B8%7D%20-%20%5Cfrac%7B1%7D%7B8%7Dy%5E%7B4%7D%20-%20%5Cfrac%7B1%7D%7B4%7D%20y%5E%7B2%7D%20%2B%20y%5D%20%7D%20%5C%2C%20dy%20)
![= \pi [ \frac{1}{2304}y^{9} - \frac{1}{40}y^{5} - \frac{1}{12} y^{3} + \frac{1}{2} y^{2}]^{2}_{0}](https://tex.z-dn.net/?f=%20%3D%20%5Cpi%20%5B%20%5Cfrac%7B1%7D%7B2304%7Dy%5E%7B9%7D%20-%20%5Cfrac%7B1%7D%7B40%7Dy%5E%7B5%7D%20-%20%5Cfrac%7B1%7D%7B12%7D%20y%5E%7B3%7D%20%2B%20%5Cfrac%7B1%7D%7B2%7D%20y%5E%7B2%7D%5D%5E%7B2%7D_%7B0%7D%20)
