Find the deriviative of the following function and specify the domain of this derviative
Use the defintion of the derivative to prove that the function
f(z)=Im z -2i
is not differentiable at 1+2i
Now I have attempted this question using the quotient Rule and ended up with something like this
Now i am not sure on how to simplfy it further. The value thats getting to me is the most is the 4z^2/(4z-i)/z^4. Hope fully some one can show me how to do it and also help on what the domain is.
For this part i know i am to use the formula
But how to do it is really confusing. I think as well that the Imz part is making it probably seem harder then it actually is.
Hopefully someone can point me in the right direction