Evaluating a triple integral Spherical

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SUMMARY

The discussion focuses on evaluating the triple integral of the function z(x²+y²+z²)⁻³/² within the constraints of the sphere defined by x²+y²+z² ≤ 4 and z ≥ 1. The correct spherical coordinates involve integrating with respect to ρ, θ, and φ, where ρ ranges from 0 to 2 and θ from 0 to 2π. The limits for φ must be determined based on the geometry of the solid, specifically noting that the z-axis limits are 1 ≤ z ≤ 2, which affects the limits of ρ as a function of φ. The discussion suggests that visualizing the problem in cylindrical coordinates may simplify the evaluation.

PREREQUISITES
  • Understanding of spherical coordinates and their application in triple integrals
  • Knowledge of cylindrical symmetry in three-dimensional integrals
  • Familiarity with trigonometric identities and their use in integration
  • Experience with evaluating limits of integration in multi-variable calculus
NEXT STEPS
  • Study the conversion between spherical and cylindrical coordinates for triple integrals
  • Learn how to visualize and sketch cross-sections of three-dimensional solids
  • Research techniques for determining limits of integration in spherical coordinates
  • Practice solving triple integrals involving cylindrical symmetry
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Students and educators in calculus, particularly those focusing on multivariable integration, as well as mathematicians seeking to deepen their understanding of triple integrals in spherical coordinates.

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Homework Statement


z(x^2+y^2+z^2)^(-3/2) where x^2+y^2+z^2 ≤ 4 and z ≥ 1





The Attempt at a Solution


So spherically this comes down to cos∅sin∅dpdθd∅
p goes from 0 to 2, theta goes from 0 to 2pi, but I don't know how to figure out what ∅ goes from? I'm trying use trig identities but I'm getting the wrong answer, so maybe this don't work since the sphere is curved?
 
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Your limits for ##\rho## aren't correct. For example, consider the part of the z-axis which is inside the solid. It's only the part where 1 ≤ z ≤ 2. This would be inconsistent with ##\rho \le 1##, yet your lower limit for ##\rho## is 0.

In this case, you have cylindrical symmetry, so try drawing a cross section of the surface through, say, the xz plane. You should be able to see pretty easily the limits of ##\phi##, and you'll have to figure out the limits of ##\rho## as a function of ##\phi##.
 
Given the bounds, it might be easier to handle in cylindrical.
 

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