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Coordinate systems for integration

Some common change in coordinate systems to evaluate integrals better and their corresponding scaling factor to convert between systems using the Jacobian:

In 2D #

  • Cartesian: dA=dxdy
  • Polar: dA=r drdθ
    • x=$r\cos\theta$
    • y=$r\sin\theta$

In 3D #

  • Cartesian: dV=dxdydz
  • Cylindrical: dV=r drdθdz
    • x=$r\cos\theta$
    • y=$r\sin\theta$
    • z=z
  • Spherical: dV=$r^2 \sin(\theta)drd\theta d\phi$
    • x=$r\sin \theta \cos\phi$
    • y=$r\sin \theta \sin\phi$
    • z=$r \cos \theta$