Triple Integral with Spherical Coordinates

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SUMMARY

The discussion focuses on evaluating the triple integral \(\int\int\int \frac{1}{\sqrt{x^{2}+y^{2}+z^{2}+3}} dV\) over the boundary B, defined as a ball of radius 2 centered at the origin. The participants utilize spherical coordinates with the substitutions \(x = p \sin \Phi \cos \Theta\), \(y = p \sin \Phi \sin \Theta\), and \(z = p \cos \Phi\). Integral limits are established as \(dp\) from 0 to 2, \(d\Phi\) from 0 to \(\pi\), and \(d\Theta\) from 0 to \(2\pi\). The main challenge discussed is simplifying the integrand after substitution, which leads to confusion and difficulty in maintaining the identity \(\sin^2 \eta + \cos^2 \eta = 1\).

PREREQUISITES
  • Understanding of triple integrals in calculus
  • Familiarity with spherical coordinates and their transformations
  • Knowledge of integral limits in multivariable calculus
  • Ability to manipulate trigonometric identities
NEXT STEPS
  • Study the process of converting Cartesian coordinates to spherical coordinates
  • Learn techniques for simplifying complex integrands in multiple integrals
  • Explore examples of triple integrals over spherical regions
  • Investigate the application of trigonometric identities in integral calculus
USEFUL FOR

Students and educators in calculus, particularly those focusing on multivariable calculus and integral evaluation techniques. This discussion is beneficial for anyone tackling triple integrals and spherical coordinate transformations.

veritaserum
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Homework Statement


Evaluate \int\int\int 1/\sqrt{x^{2}+y^{2}+z^{2}+3} over boundary B, where B is the ball of radius 2 centered at the origin.


Homework Equations


Using spherical coordinates:
x=psin\Phicos\Theta
y=psin\Phisin\Theta
z=pcos\Phi

Integral limits:
dp - [0,2]
d\Phi - [0,\pi]
d\Theta - [0,2\pi]

The Attempt at a Solution


I am just having trouble finding a good substitution for the integrand. When I substitute x,y, and z with the spherical substitutions, I just get a huge jumbled mess that I can't make any sense of.
 
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whoops sorry, the integrand should be
\frac{dV}{\sqrt{x^{2}+y^{2}+z^{2}+3}}
 
veritaserum said:
When I substitute x,y, and z with the spherical substitutions, I just get a huge jumbled mess that I can't make any sense of.

Show us. And keep in mind that \sin^2\eta+\cos^2\eta=1.
 
lol even trying to type that out is a huge jumbled mess in itself. i understand the property you gave me, it's just that i am not able to factor out enough terms such that i leave that identity intact.
 

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