Triple integration over portion of Sphere

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Homework Help Overview

The discussion revolves around a problem involving triple integration over a portion of a sphere, specifically utilizing spherical coordinates and the spherical Jacobian. Participants are comparing results obtained through different coordinate systems, including cylindrical and spherical coordinates.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants are attempting to solve the integration problem using spherical coordinates and are discussing the results obtained. There are questions regarding the correctness of integration steps and the implications of different upper bounds on the results.

Discussion Status

The discussion is ongoing, with participants sharing their results and questioning each other's calculations. Some guidance has been offered regarding the use of integration by parts and the need to verify derivatives, but no consensus has been reached on the final answer.

Contextual Notes

There are references to specific integration bounds and the potential impact of these bounds on the results, indicating that assumptions about the limits of integration are being examined. Additionally, there is a mention of the need for participants to improve their use of LaTeX for clarity in mathematical expressions.

nysnacc
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Homework Statement


upload_2016-10-3_19-5-13.png


Homework Equations


spherical Jacobean

The Attempt at a Solution


I have (sorry, have to capture my work, too hard to type)
upload_2016-10-3_19-6-20.png


then the integration of p3 ep2 = 1/2 ep2 (p2-3/2) ??
 
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The answer I got using cylindrical was eπ/8,
but here, using the spherical, I got π(e+3)/64
 
nysnacc said:

Homework Statement


View attachment 106917

Homework Equations


spherical Jacobean

The Attempt at a Solution


I have (sorry, have to capture my work, too hard to type)
View attachment 106918

****************************************************************
Your material is NOT too hard to type; you just need to learn how to use LaTeX. That does take some effort, though.
*****************************************************************

then the integration of p3 ep2 = 1/2 ep2 (p2-3/2) ??

No. You can check that for yourself, by showing that the derivative is not ##r^3 \exp(r^2)##.

Do integration by parts.

BTW: I get ##\pi/8## using spherical coordinates.
 
π/8 not πe/8 ?
 
nysnacc said:
π/8 not πe/8 ?

I wrote exactly what I meant.

If you had a different upper bound of ##r = a## instead of ##r = 1## you would, indeed, get an exponential in the answer.
 

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