例如
\documentclass[14pt,twoside]{extreport}
\renewcommand{\baselinestretch}{1.5}
\usepackage[utf8]{inputenc}
\usepackage{graphicx}
\usepackage[a4paper,width=150mm,top=25mm,bottom=25mm,bindingoffset=6mm]{geometry}
\usepackage{fancyhdr}
\pagestyle{fancy}
\fancyhead{}
\fancyhead{}
\fancyhead[RO,LE]{\small\leftmark }
\usepackage{amsfonts}
\usepackage{graphicx}
\usepackage{amsthm}
\usepackage{amsmath}
\usepackage[english]{babel}
\begin{document}
First, we compute the following products:
\begin{align*}
R_2R_5&=a_2 a_5 t^2+\left(a_5 b_2+a_2 b_5\right) t+b_2 b_5,\\
R_2 R_3 R_5&=a_2 a_3 a_5 t^3+\left(a_3 a_5 b_2+a_2 a_5 b_3+a_2 a_3 b_5\right) t^2+\left(a_5 b_2 b_3+a_2 b_5 b_3+a_3 b_2 b_5\right) t\\
&+b_2 b_3 b_5,\\
R_4 R_6&=a_4 a_6 t^2+\left(a_6 b_4+a_4 b_6\right) t+b_4 b_6,\\
R_3 R_4 R_6&=a_3 a_4 a_6 t^3+\left(a_4 a_6 b_3+a_3 a_6 b_4+a_3 a_4 b_6\right) t^2+\left(a_6 b_3 b_4+a_3 b_6 b_4+a_4 b_3 b_6\right) t\\
&+b_3 b_4 b_6,
\end{align*}
By replacement, ordering by powers of t and identifying, we obtain a system whose solutions describe the number of straight lines situated on the "reliability" hypersurface. We write the system ordering by the coefficients of the powers of degree from zero to five,relative to t:
\begin{align*}
b_7&=b_2 b_5+ b_2 b_3 b_5 - b_2 b_3 b_6 b_5 + b_3 b_6 b_5 - b_2 b_4 b_6 b_5 + b_2 b_3 b_4 b_6 b_5 - b_3 b_4 b_6 b_5 + b_3 b_4 b_6 + b_4 b_6,
\end{align*}
Starting from the last equation, at least one of the numbers $a_i$; $i = 2,\ldots , 6$ must be zero
(number of cases: $C_1^5 + C_2^5 + C_3^5 + C_4^5 = 30)$. So the straight-lines are parallel to some hyperplane of coordinates. The first equation shows that at t = 0, point $(b_2,\ldots, b_7)$ is on the "reliability" hypersurface. This remark requires the following procedure: we choose arbitrarily $b_2, \ldots ,b_6$, and compute $b_7$. We replace the values $(b_2,\ldots, b_7)$ in the remaining equations. If the new system, in unknown $(a_2,\ldots, a_7)$ , it has a solution with at least a nonzero component, then there exists one straight line passing through the point $(b_2,\ldots, b_7)$
and lying on the "reliability" hypersurface. Explicitly, after solving the algebraic system, we have the following cases:
\end{document}
结果是这样的
如何在文本限制内调整方程？
谢谢您的帮助
答案1
一般来说，手动分解方程式要好得多。替换amsmath with its extensionmathtools , here a way to nicely break the equations with themultlined` 环境：
\documentclass[14pt,twoside]{extreport}
\renewcommand{\baselinestretch}{1.5}
\usepackage[utf8]{inputenc}
\usepackage{graphicx}
\usepackage[a4paper,width=150mm,top=25mm,bottom=25mm,bindingoffset=6mm, showframe]{geometry}
\usepackage{fancyhdr}
\pagestyle{fancy}
\fancyhead{}
\fancyhead{}
\fancyhead[RO,LE]{\small\leftmark }
\usepackage{amsfonts}
\usepackage{graphicx}
\usepackage{amsthm}
\usepackage{mathtools}
\usepackage[english]{babel}
\begin{document}
First, we compute the following products:
\begin{align*}
R_2R_5&=a_2 a_5 t^2+\left(a_5 b_2+a_2 b_5\right) t+b_2 b_5,\\
R_2 R_3 R_5&=\begin{multlined}[t] a_2 a_3 a_5 t^3+\left(a_3 a_5 b_2+a_2 a_5 b_3+a_2 a_3 b_5\right) t^2 \\[-1ex]
+\left(a_5 b_2 b_3+a_2 b_5 b_3+a_3 b_2 b_5\right) + b_2 b_3 b_5,t \end{multlined} \\
R_4 R_6&=a_4 a_6 t^2+\left(a_6 b_4+a_4 b_6\right) t + b_4 b_6,\\
R_3 R_4 R_6&=\begin{multlined}[t] a_3 a_4 a_6 t^3+\left(a_4 a_6 b_3+a_3 a_6 b_4+a_3 a_4 b_6\right) t^2 \\[-1ex]
+\left(a_6 b_3 b_4+a_3 b_6 b_4+a_4 b_3 b_6\right) t + b_3 b_4 b_6. \end{multlined}
\end{align*}
By replacement, ordering by powers of $ t $ and identifying, we obtain a system whose solutions describe the number of straight lines situated on the "reliability" hypersurface. We write the system ordering by the coefficients of the powers of degree from zero to five,relative to $ t $:
\begin{multline*}
b_7=b_2 b_5+ b_2 b_3 b_5 - b_2 b_3 b_6 b_5 + b_3 b_6 b_5 - b_2 b_4 b_6 b_5 \\[-1ex]
+ b_2 b_3 b_4 b_6 b_5 - b_3 b_4 b_6 b_5 + b_3 b_4 b_6 + b_4 b_6.
\end{multline*}
Starting from the last equation, at least one of the numbers $a_i$; $i = 2,\ldots , 6$ must be zero
(number of cases: $C_1^5 + C_2^5 + C_3^5 + C_4^5 = 30)$. So the straight-lines are parallel to some hyperplane of coordinates. The first equation shows that at $ t = 0 $, point $(b_2,\ldots, b_7)$ is on the "reliability" hypersurface. This remark requires the following procedure: we choose arbitrarily $b_2, \ldots ,b_6$, and compute $b_7$. We replace the values $(b_2,\ldots, b_7)$ in the remaining equations. If the new system, in unknown $(a_2,\ldots, a_7)$ , it has a solution with at least a nonzero component, then there exists one straight line passing through the point $(b_2,\ldots, b_7)$ and lying on the "reliability" hypersurface. Explicitly, after solving the algebraic system, we have the following cases:
\end{document}
