multi case function in latex
\documentclass{article}
\usepackage{amsmath}
\usepackage{multirow}
\begin{document}
\[
X(m,n) = \left\{\begin{array}{@{}lr@{}}
\multirow{2}{*}{x(n),} & \text{for }0\leq n\leq 1\\
& \text{or }0\leq n\leq 1\\
x(n-1), & \text{for }0\leq n\leq 1\\
x(n-1), & \text{for }0\leq n\leq 1
\end{array}\right\} = xy
\]
\end{document}