Answer:
The volume of the solid is 714.887 units³
Step-by-step explanation:
* Lets talk about the shell method
- The shell method is to finding the volume by decomposing
a solid of revolution into cylindrical shells
- Consider a region in the plane that is divided into thin vertical
rectangle
- If each vertical rectangle is revolved about the y-axis, we
obtain a cylindrical shell, with the top and bottom removed.
- The resulting volume of the cylindrical shell is the surface area
of the cylinder times the thickness of the cylinder
- The formula for the volume will be: V =
,
where 2πx · f(x) is the surface area of the cylinder shell and
dx is its thickness
* Lets solve the problem
∵ y = ![x^{\frac{5}{2}}](https://tex.z-dn.net/?f=x%5E%7B%5Cfrac%7B5%7D%7B2%7D%7D)
∵ The plane region is revolving about the y-axis
∵ y = 32 and x = 0
- Lets find the volume by the shell method
- The definite integral are x = 0 and the value of x when y = 32
- Lets find the value of x when y = 0
∵ ![y = x^{\frac{5}{2}}](https://tex.z-dn.net/?f=y%20%3D%20x%5E%7B%5Cfrac%7B5%7D%7B2%7D%7D)
∵ y = 32
∴ ![32=x^{\frac{5}{2}}](https://tex.z-dn.net/?f=32%3Dx%5E%7B%5Cfrac%7B5%7D%7B2%7D%7D)
- We will use this rule to find x, if
, where c
is a constant
∴ ![x=(32)^{\frac{2}{5}}=4](https://tex.z-dn.net/?f=x%3D%2832%29%5E%7B%5Cfrac%7B2%7D%7B5%7D%7D%3D4)
∴ The definite integral are x = 0 , x = 4
- Now we will use the rule
∵ ![V = \int\limits^a_b {2\pi}xf(x) \, dx](https://tex.z-dn.net/?f=V%20%3D%20%5Cint%5Climits%5Ea_b%20%7B2%5Cpi%7Dxf%28x%29%20%5C%2C%20dx)
∵ y = f(x) = x^(5/2) , a = 4 , b = 0
∴ ![V=2\pi \int\limits^4_0 {x}.x^{\frac{5}{2}}\, dx](https://tex.z-dn.net/?f=V%3D2%5Cpi%20%5Cint%5Climits%5E4_0%20%7Bx%7D.x%5E%7B%5Cfrac%7B5%7D%7B2%7D%7D%5C%2C%20dx)
- simplify x(x^5/2) by adding their power
∴ ![V = 2\pi \int\limits^4_0 {x^{\frac{7}{2}}} \, dx](https://tex.z-dn.net/?f=V%20%3D%202%5Cpi%20%5Cint%5Climits%5E4_0%20%7Bx%5E%7B%5Cfrac%7B7%7D%7B2%7D%7D%7D%20%5C%2C%20dx)
- The rule of integration of ![x^{n} is ==== \frac{x^{n+1}}{(n+1)}](https://tex.z-dn.net/?f=x%5E%7Bn%7D%20is%20%3D%3D%3D%3D%20%5Cfrac%7Bx%5E%7Bn%2B1%7D%7D%7B%28n%2B1%29%7D)
∴
from x = 0 to x = 4
∴
from x = 0 to x = 4
- Substitute x = 4 and x = 0
∴ ![V=2\pi[\frac{2}{9}(4)^{\frac{9}{2}}-\frac{2}{9}(0)^{\frac{9}{2}}}]=2\pi[\frac{1024}{9}-0]](https://tex.z-dn.net/?f=V%3D2%5Cpi%5B%5Cfrac%7B2%7D%7B9%7D%284%29%5E%7B%5Cfrac%7B9%7D%7B2%7D%7D-%5Cfrac%7B2%7D%7B9%7D%280%29%5E%7B%5Cfrac%7B9%7D%7B2%7D%7D%7D%5D%3D2%5Cpi%5B%5Cfrac%7B1024%7D%7B9%7D-0%5D)
∴ ![V=\frac{2048}{9}\pi=714.887](https://tex.z-dn.net/?f=V%3D%5Cfrac%7B2048%7D%7B9%7D%5Cpi%3D714.887)
* The volume of the solid is 714.887 units³