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Viewing Version 1 of 'Cauchy-Riemann equations (polar coordinates)'
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Title of object: Cauchy-Riemann equations (polar coordinates)
Canonical Name: CauchyRiemannEquationsPolarCoordinates
Type: Definition

Created on: 2003-11-15 12:05:14
Modified on: 2003-11-15 12:05:14

Creator: Daume
Modifier: Daume
Author: Daume

Classification: msc:30E99

Revision comment (for changes between this and next version):

Changes for correction #2825 ('undefined terms').

Preamble:

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Content:

Suppose $A$ is an open set in $\mathbb{C}$ and $f=u(r,\theta)+iv(r,\theta): A\subset\mathbb{C} \to \mathbb{C}$ is a function. If the derivative of $f(z)$ exists at $z_0=(r_0,\theta_0)$. Then the functions $u$, $v$ at $z_0$ satisfy:
\begin{eqnarray*}
\frac{\partial u}{\partial r} & = & \frac{1}{r}\frac{\partial v}{\partial \theta}\\
\frac{\partial v}{\partial r} & = & -\frac{1}{r}\frac{\partial u}{\partial \theta}
\end{eqnarray*}
which are called \emph{Cauchy-Riemann equations} in polar form.