seichan
Nov17-08, 01:12 AM
1. The problem statement, all variables and given/known data
A volcano fills the volume between the graphs z = 0 and z =1/(x^2+y^2)^24, and outside the cylinder x^2+y^2=1 Find the volume of this volcano.
2. Relevant equations
This is a triple integral to be evaluated in cylindrical coordinates.
3. The attempt at a solution
Alright, so, this is what I've done. I don't understand what I'm doing wrong. I set up a triple integral, the limits of integration as follows:
z goes from 0 to 1
theta goes from 0 to 2pi
and r goes from 1 to z^-1/48 (outside the unit circle, but between the other graphs)
I first integrate with respect to r. I get r^2/2, evaluated between z^-1/48 and 1. This gives the integrand (z^-1/2304)/2-1/2. Then, I integrated with respect to z. This gives the answer ((2304z^(2303/2304)/2303)/2)-z/2. Then, this is evaluated from 0 to 1. This gives (2304/2303)/2-1/2, or, (1/2303)/2. This is integrated with respect to theta, giving (theta/2303)/2. Evaluated at 2pi, this results in (2pi/2303)/2. However, my homework software has told me this is wrong multiple times. Where am I going wrong? Thank you for any assistance.
A volcano fills the volume between the graphs z = 0 and z =1/(x^2+y^2)^24, and outside the cylinder x^2+y^2=1 Find the volume of this volcano.
2. Relevant equations
This is a triple integral to be evaluated in cylindrical coordinates.
3. The attempt at a solution
Alright, so, this is what I've done. I don't understand what I'm doing wrong. I set up a triple integral, the limits of integration as follows:
z goes from 0 to 1
theta goes from 0 to 2pi
and r goes from 1 to z^-1/48 (outside the unit circle, but between the other graphs)
I first integrate with respect to r. I get r^2/2, evaluated between z^-1/48 and 1. This gives the integrand (z^-1/2304)/2-1/2. Then, I integrated with respect to z. This gives the answer ((2304z^(2303/2304)/2303)/2)-z/2. Then, this is evaluated from 0 to 1. This gives (2304/2303)/2-1/2, or, (1/2303)/2. This is integrated with respect to theta, giving (theta/2303)/2. Evaluated at 2pi, this results in (2pi/2303)/2. However, my homework software has told me this is wrong multiple times. Where am I going wrong? Thank you for any assistance.