用nicematrix
的方案一:
\documentclass{article}
\usepackage{libertinus-otf}
\usepackage{nicematrix}
\usepackage{tikz}
\usepackage{lipsum}
\begin{document}
\lipsum[2]
\[
X =
\begin{pNiceMatrix}[extra-margin=7pt,cell-space-limits=.125cm]
1\Block[borders={bottom,left,tikz=densely dashed}]{1-1}{} & 0 & 2 & 0 & -3 \\
0 & 1\Block[borders={bottom,left,tikz=densely dashed}]{1-2}{} & -1 & 0 & -4 \\
0 & 0 & 0 & 3\Block[borders={bottom,left,tikz=densely dashed}]{1-2}{} & 5 \\
0 & 0 & 0 & 0 & 0 \\
\end{pNiceMatrix}
= Y
\]
\lipsum[2]
\end{document}
问 如何画图中的阶梯形矩阵?虚线得画上喔