latex 转义字符 | esapce characters in latex

如下Latex代码编译会出错：


\begin{eqnarray}
  a &=& b \\
  [a] &=& [b] \\
\end{eqnarray}

原因是[a]被识别成了\\后跟的长度，于是报错，于是需要把[转义，写成{[}就好了。

The following Latex code won't compile:


\begin{eqnarray}
  a &=& b \\
  [a] &=& [b] \\
\end{eqnarray}

and the reason is that [a] is recognized as the length parameter of \\. So [ should be escaped, if written as {[} there won't be error any more.

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