将 12*12 矩阵居中对齐

Question

我已经使用 \begin{bmatrix} 和 \setcounter{MaxMatrixCols}{20} 来获取该矩阵。我如何将其分配到中心或者缩放该矩阵.....？

Answer 1

我会做类似以下的事情（不追求美观）

\documentclass{article}
\usepackage{amsmath,amsfonts}
\begin{document}
We did symmetric matrix stuff. Let $K_1, K_2, K_3, K_4$ be symmetric matrices defined as 
\[
\mathbb{J} = \begin{bmatrix}1&-1\\-1&1\end{bmatrix},\ 
K_2 = \begin{bmatrix} \frac{12EI}{L^2}&\frac{12EI}{L^2}&\frac{12EI}{L^2}&\frac{12EI}{L^2}\\
                      \star&\frac{12EI}{L^2}&\frac{12EI}{L^2}&\frac{12EI}{L^2}\\
                      \star&\star&\frac{12EI}{L^2}&\frac{12EI}{L^2}\\
                      \star&\star&\star&\frac{12EI}{L^2}
      \end{bmatrix},\
K_3 = \begin{bmatrix} \frac{12EI}{L^2}&\frac{12EI}{L^2}&\frac{12EI}{L^2}&\frac{12EI}{L^2}\\
                      \star&\frac{12EI}{L^2}&\frac{12EI}{L^2}&\frac{12EI}{L^2}\\
                      \star&\star&\frac{12EI}{L^2}&\frac{12EI}{L^2}\\
                      \star&\star&\star&\frac{12EI}{L^2}
      \end{bmatrix}
\]
then 
\[
K = \begin{bmatrix}\frac{EA}{L}\mathbb{J}&&&\\&K_2&&\\&&K_3&\\&&&\frac{JG}{L}\mathbb{J}\end{bmatrix}
\]

\end{document}