For the region bounded by x=y^2 and x=4 revolved about the line x=5 , we may apply Washer method for the integral application for the volume of a solid.
The formula for the Washer Method is:
V = pi int_a^b [(f(x))^2-(g(x))^2]dx
or
V = pi int_a^b [(f(y))^2-(g(y))^2]dy
where f as function of the outer radius
g as a function of the inner radius
To determine which form we use, we consider the horizontal rectangular strip representation that is perpendicular to the axis of rotation as shown on the attached image. The given strip have a thickness of "dy " which is our clue to use the formula:
V = pi int_a^b [(f(y))^2-(g(y))^2]dy
For each radius, we follow the x_2-x_1 . We have x_2=5 on both radius since it is a distance between the axis of rotation and each boundary graph.
For the inner radius, we have: g(y) = 5-4=1 .
For the outer radius, we have: f(y) = 5-y^2 .
Then the boundary values of y are a=-2 and b =2 .
Then the integral will be:
V = pi int_(-2)^2 [(5-y^2)^2-(1)^2]dy
Exapnd using the FOIL method on:
(5-y^2)^2 = (5-y^2)(5-y^2)= 25-10y^2+y^4 and 1^2=1
The integral becomes:
V = pi int_(-2)^2 [25-10y^2+y^4-1]dy
Simplify: V = pi int_(-2)^2 [24-10y^2+y^4]dy
Apply basic integration property:
int (u+-v+-w)dy = int (u)dy+-int (u)dy+-int (v)dy+-int (w)dy
V = pi [int_(-2)^2 (24)dy -int_(-2)^2 (10y^2)dy+int_(-2)^2 (y^4) dy]
Apply basic integration property: int c dx = cx , int c f(x) dx = c int f(x)dx , and Power rule for integration: int y^n dx = y^(n+1)/(n+1) .
V = pi [24y -10y^3/3+ y^5/5]|_(-2)^2
Apply the definite integral formula: int _a^b f(x) dx = F(b) - F(a) .
V = pi [24(2) -10(2)^3/3+ (2)^5/5] -pi [24(-2) -10(-2)^3/3+ (-2)^5/5]
V = pi [48 -80/3+ 32/5] -pi [-48 -(-80)/3+ (-32)/5]
V = pi [48 -80/3+ 32/5 +48 -80/3+32/5]
V = pi [96 -160/3+ 64/5]
V = pi [1440/15 -800/13+ 192/15]
V = 832/15pi
or V =174.25 (approximated value)
Sunday, September 11, 2016
x=y^2 , x=4 Find the volume of the solid generated by revolving the region bounded by the graphs of the equations about the line x = 5
Subscribe to:
Post Comments (Atom)
Why is the fact that the Americans are helping the Russians important?
In the late author Tom Clancy’s first novel, The Hunt for Red October, the assistance rendered to the Russians by the United States is impor...
-
Friar Lawrence plays a significant role in Romeo and Juliet's fate and is responsible not only for secretly marrying the two lovers but ...
-
Suppose that the average daily food consumption $F$ of a herbivorous mammal with body weight $x$, where both $F$ and $x$ are measured in pou...
-
Resourceful: Phileas Fogg doesn't let unexpected obstacles deter him. For example, when the railroad tracks all of a sudden end in India...
-
Pablo Neruda's "Ode to My Socks" is full of figurative language, including similes and metaphors. Similes are figurative compa...
-
In the late author Tom Clancy’s first novel, The Hunt for Red October, the assistance rendered to the Russians by the United States is impor...
-
Evaluate $\displaystyle \int x^2 \cos mx dx$ by using Integration by parts. If we let $u = x^2$ and $dv = \cos mx dx$, then $d...
-
At the beginning of the Victorian period, science was generally in accord with religion, and the study of nature was conducted in such a way...
No comments:
Post a Comment