使用包的简短示例witharrows
。
\documentclass[12pt,a4paper]{article}
\usepackage{amsmath,amssymb}
\usepackage{witharrows}
\begin{document}
$\begin{WithArrows}
A &= B \Arrow{explanation1} \\
& = D\Arrow{explanation2}\\
&=F\Arrow{explanation3}\\
&=K
\end{WithArrows}$
\end{document}