\documentclass{report}
\usepackage{tabulary}
\setlength\tymin{10pt}
\setlength\tymax{\maxdimen}
\usepackage{xepersian}
\settextfont{Adobe Arabic}
\begin{document}

\begin{equation*}
\left\{
\begin{array}{rl}
1 \quad  x\in A\\
0 \quad x \in A
\end{array} \right.
\end{equation*}
\end{document}