LaTeX Forum

\documentclass[pdftex,a4paper,twoside]{article}

\usepackage{ngerman}
\usepackage[latin1]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsmath}

\begin{document}

	\begin{align*}
		K(f)=\{z\in \mathbb{C} \;|\; \left( f^k(z) \right)_{k\in \mathbb{C}} \text{ist beschränkt}\}
	\end{align*}
			
\end{document}

\documentclass{article}

\usepackage[latin1]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsmath}

\begin{document}
\begin{align*}
K(f)=\left\{z\in\mathbb{C}\;\middle|\;\left( f^k(z)\right)_{k\in\mathbb{C}}\text{ist beschränkt}\right\}
\end{align*}
\end{document}