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我有这个等式:
\documentclass[a4paper,12pt]{article}
\usepackage{amsmath}
\title{}
\author{}
\date{}
\begin{document}
\begin{equation}
\frac{u(x,t)-u(x,t-k)}{k}=c\frac{u(x+h,t)-2u(x,t)+u(x-h,t)}{h^2}+(\frac{u(x+h,t)-u(x-h,t)}{2h})(\frac{c(x+h,t)-c(x-h,t)}{2h}) \\
\end{equation}
\end{document}
问题是它超出了页面范围。所以我尝试了:
\begin{align}
\frac{u(x,t)-u(x,t-k)}{k} \\
=& c\frac{u(x+h,t)-2u(x,t)+u(x-h,t)}{h^2}+(\frac{u(x+h,t)-u(x-h,t)}{2h})(\frac{c(x+h,t)-c(x-h,t)}
{2h})
\end{align}
这似乎也不起作用。有什么建议吗?
答案1
您可以使用multline
。
\documentclass[a4paper,12pt]{article}
\usepackage{amsmath}
\title{}
\author{}
\date{}
\begin{document}
\begin{multline}
\frac{u(x,t)-u(x,t-k)}{k}
= c\frac{u(x+h,t)-2u(x,t)+u(x-h,t)}{h^2}\\
+\left(\frac{u(x+h,t)-u(x-h,t)}{2h}\right)
\left(\frac{c(x+h,t)-c(x-h,t)}{2h}\right)
\end{multline}
\begin{multline}
\frac{u(x,t)-u(x,t-k)}{k}
= c\frac{u(x+h,t)-2u(x,t)+u(x-h,t)}{h^2}\\
+\Bigl(\frac{u(x+h,t)-u(x-h,t)}{2h}\Bigr)
\Bigl(\frac{c(x+h,t)-c(x-h,t)}{2h}\Bigr)
\end{multline}
\end{document}