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1. The problem statement, all variables and given/known data

The region R bounded by y = x[tex]^{2}[/tex], y = 0, x = 1 and x = 4 is rotated about x = −1

2. Relevant equations

i know that these equations take on the form of [tex]\pi\int_a^b \\((outer radius)^{2} - (inner radius)^{2})\\,dx[/tex]

3. The attempt at a solution

so i set the problem up like this and still cant get the correct answer which is [tex]339\pi/2[/tex]

-for the bounds i know that the integral i want to evaluate is between 0 and 16 based on the line y=0 and the function [tex]y=x^{2}[/tex] evaluated at x=4.

-the outer radius is [tex]1+\sqrt{y}[/tex] and the inner radius is just 1

[tex]\pi\int_0^{16}\\ (1+\sqrt{y})^2-(1)^2\\,dy[/tex]

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# Homework Help: Volume integration using washermethod

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