(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Rewrite this in terms of f, f, ∂f/∂x, and x:

∂f(x,y)/∂(%Δx) = ∂f(x,y)/∂(d log(x) )

2. Relevant equations

∂(%Δf(x,y))/∂(%Δx) = ∂logf(x,y)/∂log(x)= ∂f(x,y)/∂x*x/f(x,y).

∂f(x,y)/∂log(x)=x∂f(x,y)/∂x

3. The attempt at a solution

I found that (%Δx) can be written as the differential of log(x):

∂f(x,y)/∂(%Δx) = ∂f(x,y)/∂(d log(x) ).

But the partial of derivative of differential of the variable throws me off. It seems like the valid problems that people may have in real world: how much the level of function changes if you increase 1% of the variable, but I can't find anything on it.

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# Homework Help: Partial derivative of function w.r.t. the percent change of the variable

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