Setting up triple integrals in different coordinates

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SUMMARY

The discussion focuses on setting up triple integrals for the function f(x,y,z) over the region defined by the cone z=√(x²+y²) for 2≤x≤7. The participants explore the conversion of integrals into Cartesian, cylindrical, and spherical coordinates. Key equations for cylindrical coordinates include x=rcosθ, y=rsinθ, and z=z, while spherical coordinates utilize ρ²=x²+y²+z², x=ρsin(φ)cos(θ), y=ρsin(φ)sin(θ), and z=ρcos(φ). The main challenge discussed is determining the correct limits of integration for each coordinate system.

PREREQUISITES
  • Understanding of triple integrals and volume integrals
  • Familiarity with Cartesian, cylindrical, and spherical coordinate systems
  • Knowledge of the equations for converting between coordinate systems
  • Ability to determine limits of integration for multi-variable functions
NEXT STEPS
  • Research how to derive limits of integration for triple integrals in cylindrical coordinates
  • Study the conversion process between Cartesian and spherical coordinates
  • Learn about the Jacobian determinant for changing variables in multiple integrals
  • Practice setting up and solving triple integrals with various functions and regions
USEFUL FOR

Students studying multivariable calculus, educators teaching integration techniques, and anyone looking to improve their skills in setting up and solving triple integrals in different coordinate systems.

anna.schweizer
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Homework Statement



Assume that f(x,y,z) is a continuous function. Let U be the region inside the cone z=√x^2+y^2 for 2≤x≤7. Set up the intregal ∫f(x,y,z)dV over U using cartesian, spherical, and cylindrical coordinates.

Homework Equations



CYLINDRICAL COORDINATES
  • x=rcosθ
  • y=rsinθ
  • z=z

SPHERICAL COORDINATES
  • ρ^2 =x^2 + y^2 + z^2
  • x = ρsin(phi)cos(θ)
  • y=ρsin(phi)sin(θ)
  • z=ρcos(phi)

The Attempt at a Solution



Do Ineed to have a function for the inner two integrals?

For my limits on integration for Cartesian coordinates are
z = x^2 + y^2 -4 and z = x^2 + y^2 -25
I DON'T KNOW FOR X
and y = 2 and y = 5

For my limits on the spherical coordinates are
θ=2π, θ=0; and ρ=2, ρ=5

I DON'T KNOW IF WHAT I'M DOING IS RIGHT OR NOT. I'M LOST :(

Please and thank you for your help!
 
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Do Ineed to have a function for the inner two integrals?
Your function is just f, you can use it as f(r, θ, z) and similar for spherical coordinates, that is fine.
Your task is to find the integral borders and to convert dV.

I DON'T KNOW FOR X
That is given in the problem statement, and please don't write in caps.

Your attempt at a solution uses equations different from the problem statement.
 

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