# How can I type the following equations in Latex?

How can I type equations as the following format?

\usepackage{amsmath}
\usepackage{cases}

\begin{document}

% without labels for different case which I need
\begin{align*}

A & \Longrightarrow B \tag{1} \\
& \Longrightarrow

\begin{cases}
G_{11}=G^{t}          &z \in C_1, z' \in C_1 \\
G_{12}=G^{<}          &z \in C_1, z' \in C_2 \\
G_{13}=G^{\rceil}     &z \in C_1, z' \in C_3
\end{cases}
\end{align*}

% another unsucessful try
\begin{align*}
A & \Longrightarrow B \tag{1} \\
& \Longrightarrow
\begin{numcases}{}
c\\
d\\
e
\end{numcases}

\end{align*}
end{document}

• Welcome to TeX.SX! Please help us help you and add a minimal working example (MWE) that illustrates your problem. Reproducing the problem and finding out what the issue is will be much easier when we see compilable code, starting with \documentclass{...} and ending with \end{document}. – albert Oct 12 at 10:05

Very dirty and inelegant. Not to be used ;-)

\documentclass{article}

\usepackage{amsmath}

\begin{document}

\begin{alignat}{2}
a &\to{} &b \\
&&c \\
&\to{}&\smash{\left\{\begin{array}{@{}c@{}} \mathstrut \\ \mathstrut \\ \mathstrut \end{array}\right.} d \\
&&e
\end{alignat}

\end{document}


Explanation: {alignat}{2} makes two pairs of rl columns, so it is basically equivalent to an array with rlrl alignment. In the first, right-aligned column I put a; in the second, left-aligned column the two arrows; in the third, right-aligned column the brace and the other letters; the fourth column is empty.