# Complex Analysis

• December 26th 2011, 10:13 AM
sinichko
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!
• December 26th 2011, 11:04 AM
FernandoRevilla
Re: Complex Analysis
Quote:

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

Ask if you have any doubt.