The Laplacian of f(r) and proof that 1 over r is harmonic (MathsCasts)
Channel: Swinburne Commons
Date: 20/05/2013

We derive a general formula for the Laplacian acting on a function f(r) then demonstrate that the Laplacian is zero in the case that f(r) = 1/r, thereby showing that 1/r is harmonic.
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Created by: Stephen Bedding