Volume bound by rho=2+2cos phi

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Homework Statement



Find the volume bounded rho=5+2cosphi

Homework Equations


dV=rho squared drho d phi d theta



The Attempt at a Solution



I am guessing this is some cylindrical shape. Theta should be 0-2pi and phi=0 pi/2
 
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You are missing a sine in your volume differential. Otherwise, what is the question? What work have you done on it so far?
 


ok typo: dV= rho squared sin phi drho dphi d theta

I cannot visualize this object to find the volume bound by rho= 5+2cos(phi)

I want to know the limits of dtheta and dphi

Integrating rho squared is easy
I am guessing the limits are 0-pi/2 for phi
and 0-2pi for theta
 
You will need to go all the way to pi for phi. Your theta bounds are correct. You don't need to worry about visualizing it - you know the volume differential:

\int dV = V
 
just to check answer: I got 653.33 Pi.

Can anyone verify if that is correct?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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