Coordinate transformation for \(\nabla^2\) operator

The equation below shows the \(\nabla^2\) operator in three-dimensional cartesian coordinates\[\nabla^2 = \frac{\partial^2}{\partial x^2} + \frac{\partial^2}{\partial y^2} + \frac{\partial^2}{\partial z^2}\]

Here is a useful Wikipedia link.

wembley  

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