Volume of Region Rotated about X-Axis Using Shell Method

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Homework Statement


use the shell method to find the volume of the region rotated about the x-axis.

Homework Equations


y=3x+10
y=x^2

The Attempt at a Solution


2∏ (integral) (0 to 25) [ (y) (sqrt(y) - (y-10)/3) dy ]
 
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whatlifeforme said:

Homework Statement


use the shell method to find the volume of the region rotated about the x-axis.


Homework Equations


y=3x+10
y=x^2


The Attempt at a Solution


2∏ (integral) (0 to 25) [ (y) (sqrt(y) - (y-10)/3) dy ]

What's the question?
 
is my attempt correct so far? just setting up the integral? becuase i keep getting the wrong answer.

my answer: 1111 (pi); correct answer: 5488pi/5
 
First off, did you draw a picture of the region, and did you draw a sketch of the solid of revolution?

If so, you should have noticed that one integral isn't going to work for this problem. The boundary function on the left changes at the point (-2, 4).
 

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