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

Assuming a counterclockwise orientation for the unit circle, calculate

∫ [itex]\frac{z+i}{z^3+2z^2}[/itex] dz

|z|=1

2. Relevant equations

f'(a)=[itex]\frac{n!}{2i\pi}[/itex]=∫[itex]\frac{f(z)}{{z-a}^(n+1)}[/itex]

???

3. The attempt at a solution

I don't understand these types of questions. What does the |z| have to do with the integral? It's written on the bottom limit of the integral in case that wasn't clear.

From the answers, it writes:

f(z)=[itex]\frac{z+i}{z+2}[/itex]

2[itex]\pi[/itex]f'(0)=[itex]\frac{\pi}{2}[/itex]+[itex]\pi[/itex]i

Edit: Nevermind. I found out how the formula works. I still don't understand what the |z| does. What would happen if it was |z|=10 for example?

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# Complex integral question

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