答案1
我会不是让矩阵比更宽\columnwidth
,因为四个看起来很复杂的单元格可以通过分解出共同元素来大大简化,如下所示。
\documentclass[twocolumn]{svjour3} % or some other suitable document class
\usepackage{amsmath} % for 'bmatrix' environment
\usepackage{newtxtext,newtxmath,lipsum}
\begin{document}
\begin{enumerate}
\addtocounter{enumi}{2} % just for this example
\item In order to study the local stability behavior
of positive equilibrium, let $J\vert_{E^*}$ be the
variational matrix evaluated at $E^*(x^*,y^*,z^*)$.
\[
J\vert_{E^*}=
\begin{bmatrix}
-ry^*\!/x
& r
& -\rho x^* \\
r & -sy^*\!/K-rx^*\!/y^* +a\psi
& -y^*\varphi \\
c_1\rho z^*
& c_2 z^*\varphi
& -\delta_1 z^* -c_2c\psi
\end{bmatrix}
\]
where $\varphi\equiv\alpha/[(1+ay^*)^2(1+bz^*)]$ and
$\psi\equiv y^*z^*\varphi$.
\end{enumerate}
\lipsum[1] % filler text
\end{document}