I am having trouble with the following question, any help would be blinding.(adsbygoogle = window.adsbygoogle || []).push({});

Find the value of ther derivative of:

(z - i)/(z + i) at i.

I tried to use the fact that f'(z0) = lim z->z0 [f(z) - f(z0)]/z - z0. I also tried using the fact that z = x + iy and rationalising the denominator, but had no joy either way.

Probably just being stupid!

Dexter

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# Help with Complex Analysis

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