How can I auto adjust an align to appear in the entire page?

Question

For example

\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}

The result is this

How can I adjust the equation within the limits of the text?

thanks for the help

I think the only way to get automatic breaking of equations is the breqn package (e.g. https://tex.stackexchange.com/questions/27365). You'll need to use the environments provided by that package though. — Torbjørn T., Jun 07 '17 at 16:14
Breaking equations is something TeX doesn't do automatically. You have to do it manually. Do you need an example of how to do it? — Michael Fraiman, Jun 07 '17 at 16:27
@Emadkareem do you mean if I can provide an example using breqn? — Michael Fraiman, Jun 07 '17 at 16:37
@Emadkareem No, beacause I prefer splitting the equations myself to give them a pretty look, i. e. I have never used this package. An example using breqn can be found in the link I have given above. — Michael Fraiman, Jun 07 '17 at 16:42
you have already broken two of the overlong lines. just move the \\ earlier in those lines. for example, in the first long line, move the break to just before +\left(a_5 .... breaking the lines yourself gives much better results than any currently existing package. — barbara beeton, Jun 07 '17 at 17:33

score 0 · Answer 1 · answered Jun 07 '17 at 17:44

It is much better to break equations by hand in general. Replacing amsmath with its extensionmathtools, here a way to nicely break the equations with themultlined` environment:

\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}

How can I auto adjust an align to appear in the entire page?

1 Answers1