# Math Help - Complex Analysis

1. ## Complex Analysis

Hello, help me please with this one.

Lets $F$be a family of analytic functions in $H=\left \{ z:Imz>0 \right \}$ which holds $f(i)=0$ and $\left | f(z) \right |\leq 1$.
Find $\underset{f\in F}{\sup }\left | f(2i) \right |$

Thanks!

2. ## Re: Complex Analysis

Originally Posted by sinichko
Hello, help me please with this one.

Lets $F$be a family of analytic functions in $H=\left \{ z:Imz>0 \right \}$ which holds $f(i)=0$ and $\left | f(z) \right |\leq 1$.
Find $\underset{f\in F}{\sup }\left | f(2i) \right |$
Look here:

complex analysis - Find $\sup\limits_{f \in F}|f(2i)|$ - Mathematics - Stack Exchange

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