Derivative of a Complex Function: Finding f'(1 + i)

nickolas2730
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1. Let f(z) = (3e2z−ie-z)/(z2−1+i) . Find f′(1 + i).


3. Should I sub (1+i) to z and then diff it by i.
Or i need to diff it by z first then sub (1+i) in it at last?

Thanks
 
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Welcome to PF, nickolas2730! :smile:

You need to diff it by z first then sub (1+i) in it at last.

Btw, you can't diff by "i". It is not a variable but a constant.
 
thank you so much!
 
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