given f=ln(x^3+y^3+z^3-3xyz)To prove df/dx+df/dy+df/dz=3/(x+y+z)(adsbygoogle = window.adsbygoogle || []).push({});

also finding (d^2/dx^2+...similar two more terms)f=? d => del

& (d^2/dx^2+...........)^2f=?

I have done the first part of the problem.The trick is to write e^f=x^3+y^3+z^3-3xyz and then to differentiate.

However the next parts are coming hopelessly huge, by the same token.

Please help.

Kolahal Bhattacharya

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# Homework Help: Partial differentiation

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