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## Homework Statement

The problem is number 4 at this link: http://college.cengage.com/mathematics/larson/calculus_early/2e/students/downloads/mws6a.pdf

The axis of revolution is 150 and the rotation is 150 degrees.

## Homework Equations

Using the shell method.

My offset is x+220.

The equations that make up the cross section:

[tex].03x^2+7.1x+350[/tex]

[tex]-6.593x+389[/tex]

[tex]389[/tex]

## The Attempt at a Solution

I planned on splitting the cross section into three parts, which are the 2 triangles and rectangles, and apply the shell method on each of these. So first I did [tex]2pi*Integral[(x+220)(.03x^2+7.1x+350)][/tex] with the bounds being -70 to -16. Then I multiplied this answer by (150/360) since it's only 150 degree rotation. In each of my applications of the shell method, the p(x), or the distance to the axis of revolution stayed at x+220. Am I on the right track if I do this for each of the 3 sections?