If the gradients of the two functions f and g are proportional everywhere in R(adsbygoogle = window.adsbygoogle || []).push({}); ^{n}, does that mean there is some differentiable function F of two variables such that F(f(x),g(x)) = 0 everywhere?

The converse is obviously true by the chain rule, so I was just wondering if this was true, too.

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# Grad f is proportional to grad g

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