如何使文本适合\调整为给定的格式？

Question

我想将以下文本放入 A4 尺寸的页面中，但文本超出了给定的格式。那么，我该如何调整它？文本在 latex 文件中的书写方式如下：

 $\langle W(E_{1}), V_{1}, E_{1}  \rangle \oplus \langle W(E_{2}), V_{2}, E_{2}  \rangle=\begin{cases}
\langle W(E_{1}), V_{1}, E_{1}  \rangle,~ \text{if}~ \langle W(E_{1}), V_{1}, E_{1}  \rangle \neq \langle W(E_{\infty}), V_{\infty}, E_{\infty} \rangle \\
\langle W(E_{2}),~ V_{2}, E_{2}  \rangle ~\text{Otherwise}
\end{cases} $
$\forall~\langle W(E_{1}), V_{1}, E_{1}  \rangle,~\langle W(E_{2}),~ V_{2}, E_{2}  \rangle \in S.$

Answer 1

我会将等式的第一部分放在显示数学环境中，并在第一个冗长的条件部分中插入换行符case。

\documentclass{article}
\usepackage{amsmath,amssymb}
\usepackage{geometry} % choose page size parameters suitably

\begin{document}

\begin{equation*}
\langle W(E_{1}), V_{1}, E_{1} \rangle \oplus 
\langle W(E_{2}), V_{2}, E_{2} \rangle =
\begin{cases}
\langle W(E_{1}), V_{1}, E_{1} \rangle,
  & \text{if } \langle W(E_{1}), V_{1}, E_{1} \rangle \\ 
  & \quad\neq \langle  W(E_{\infty}), V_{\infty}, E_{\infty} \rangle \\
\langle W(E_{2}), V_{2}, E_{2} \rangle 
  &\text{otherwise}
\end{cases}
\end{equation*}
for all $\langle W(E_{1}), V_{1}, E_{1}\rangle, 
\langle W(E_{2}), V_{2}, E_{2} \rangle \in S$.

\end{document}

Answer 2

使用\multline：

\documentclass[a4paper]{article}

\usepackage{amsmath}

\begin{document}

\begin{multline*}
  \langle W(E_1), V_1, E_1 \rangle \oplus \langle W(E_2),
  V_2, E_2 \rangle =\\
  \begin{cases}
    \langle W(E_1), V_1, E_1 \rangle & \text{if $\langle W(E_1),
    V_1, E_1 \rangle \neq \langle W(E_\infty), V_\infty,
    E_\infty \rangle$}\\
    \langle W(E_2), V_2, E_2 \rangle & \text{otherwise}
  \end{cases}
\end{multline*}
$\forall\langle W(E_1), V_1, E_1 \rangle, \langle W(E_2),
V_2, E_2 \rangle \in S$.

\end{document}