\documentclass[UTF8]{ctexart}
\usepackage{amsmath}
\begin{document}
\begin{align}\left\{\begin{aligned}
x&=eq1\\
y&=eq2+1
\end{aligned}\right.\end{align}
\end{document}
这段代码可以加大括号,
\documentclass[UTF8]{ctexart}
\usepackage{amsmath}
\begin{document}
\begin{align}
x&=eq1 \label{eqsystem1} \\
y&=eq2+1 \label{eqsystem2}
\end{align}
\end{document}
这段代码可以加多行编号,但把他们合起来,
\documentclass[UTF8]{ctexart}
\usepackage{amsmath}
\begin{document}
\begin{align}\left\{\begin{aligned}
x&=eq1 \label{eqsystem1} \\
y&=eq2+1 \label{eqsystem2}
\end{aligned}\right.\end{align}
\end{document}
就报错`Package amsmath Error: Multiple label's: label 'eqsystem1' will be lost.'什么原因?怎么结合起来?
\documentclass[UTF8]{ctexart}
\usepackage{amsmath}
\usepackage{cases}
\begin{document}
\begin{numcases}{}
x_1&=eq1 \label{eqsystem1} \\
x_2+1&=eq2 \label{eqsystem2}
\end{numcases}
\end{document}
详细总结 https://blog.csdn.net/qq_34288751/article/details/118075210
圈出来的大括号不能少