- #1
talk2glenn
Homework Statement
The region bounded by x = 1 - y4, is rotated about the line y = -4.
The volume of the resulting solid is:
Homework Equations
Area of a circle: [itex]\pi[/itex]r2
Washer method solution: [itex]\int_a^{b} pi*[f(x)^2-g(x)^2][/itex]
The Attempt at a Solution
I divided the covered region into two circles: outer with R = 4 + y and inner with r = 4. Then solved using washer method, on the integral from 0 to 1 with respect to x.
[itex]\pi\int_0^{1} [4+(1-x)^{1/4}]^2-4^2dx = 106\pi/15[/itex]
Told this is wrong by the computer. Very frustrating, as I can see no other way to set up this integral, having drawn the diagrams. Any idea what I'm doing wrong? Thanks in advance :)