Hi, so I'm trying to solve Laplace's equation by separation of variables, and there's a basic step I'm not understanding with regards to the product rule.(adsbygoogle = window.adsbygoogle || []).push({});

Given

A product rule (i think) is taken to make the first term easier to deal with and we get

I'm just having trouble understanding what the derivatives of f and g are. And am I correct in saying that f = 1/r*partial wrt r

g = r * partial phi wrt r

Thank you

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# Homework Help: Product Rule with Partial Derivatives

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