Summary of Triple Integrals in Cylindrical and Spherical Coordinates

Essential Concepts

  • To evaluate a triple integral in cylindrical coordinates, use the iterated integral
  • To evaluate a triple integral in spherical coordinates, use the iterated integral

Key Equations

  • Triple integral in cylindrical coordinates
    [latex]\underset{B}{\displaystyle\iiint} g(x,y,z)dV=\underset{B}{\displaystyle\iiint} g(r\cos\theta,r\sin\theta,z)r dr d\theta dz=\underset{B}{\displaystyle\iiint} f(r,\theta,z)r dr d\theta dz=[/latex]
  • Triple integral in spherical coordinates
    [latex]\underset{B}{\displaystyle\iiint} f(\rho,\theta,\varphi)\rho^{2}\sin\varphi{d}\rho{d}\varphi{d}\theta=\displaystyle\int_{\varphi=\gamma}^{\varphi=\psi}\displaystyle\int_{\theta=\alpha}^{\theta=\beta}\displaystyle\int_{\rho=a}^{\rho=b} \rho^{2}\sin\varphi{d}\rho{d}\varphi{d}\theta[/latex]

Glossary

triple integral in cylindrical coordinates
the limit of a triple Riemann sum, provided the following limit exists:[latex]{\displaystyle\lim_{l,m,n\to\infty}{\sum_{i=1}^{l}}{\displaystyle\sum_{j=1}^{m}}{\displaystyle\sum_{k=1}^{n}f({r^{*}}_{i,j,k}, {{\theta}^{*}}_{i,j,k}, {{z}^{*}}_{i,j,k}){r^{*}}_{i,j,k}{\Delta}r{\Delta}{\theta}{\Delta}{z}}}[/latex]
triple integral in spherical coordinates
the limit of a triple Riemann sum, provided the following limit exists: [latex]{\displaystyle\lim_{l,m,n\to\infty}{\displaystyle\sum_{i=1}^{l}}{\displaystyle\sum_{j=1}^{m}}{\displaystyle\sum_{k=1}^{n}f({{\rho}^{*}}_{i,j,k}, {{\theta}^{*}}_{i,j,k}, {{\varphi}^{*}}_{i,j,k})({{\rho}^{*}}_{i,j,k})^{2}\sin{\varphi}{\Delta}{\rho}{\Delta}{\theta}{\Delta}{\varphi}}}[/latex]