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

The only thing given is f(z)=x. However, I am under the assumption that z is a complex variable where z=x+iy. I'm also assuming that x is a real variable.

In this example, I know that f(z)=x is not differentiable with respect to z because it does not satisfy the Cauchy-Riemann Equations but I need to prove this using the limit definition of the derivative.

2. Relevant equations

I used the definition of the limit i.e. limit as h→0 [f(x+h)-f(x)]/h however I'm not quite sure what f(x+h) translates into in this problem.

3. The attempt at a solution

this may be a straight forward question that I'm over thinking but I get lim Δz→0 [Δx/Δz] which does not exist. Is that correct?

This is my first post. I don't know how to enter math notation that is easier to read. Help with that would also be appreciated.

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# Is f(z)=x differentiable with respect to z?

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