答案1
快速解决:
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{align*}
A^2 &= A, & B^2 &= C, & C^2 &= B,\\
AB &= B, & AC &= C, & BC &= A,
\end{align*}
\end{document}
答案2
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{alignat}{4} A^2 &= A, & \quad & B^2 &= C, &\quad& C^2 &= B,\\AB &= B,&& AC &= C,&& BC &= A, \end{alignat}
\end{document}