alignequationshorizontal alignmentnumberingsubequations
The following code
\begin{equation} \label{eq:test}
\begin{aligned}
A=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\\
B=BBBBBBBBBBBBBBBB\\
C=CCCCC, D=DDDDDDD\\
E=EEEEE, F=FFFFFFF
\end{aligned}
\end{equation}
Alligns the equations from right while I need them to be at the center. Using gather does not allow me to give number to my equation. What is the standard way to implement what I intend to do?
In relation to the comments I want to answer this question.
First of all to allow page breaks inside equations you have to set the command \allowdisplaybreaks. Without setting this one no page break occurs.
Using a simple align-environment. Of course as @DavidCarlisle suggested you can use the star variant to suppress the numbering and set a specific tag by \tag.
The environment split can't handle page breaks.
\documentclass{article}
\usepackage{amsmath}
\usepackage{kantlipsum}
\usepackage{showframe}
\allowdisplaybreaks
\begin{document}
\kant[1-3]
\begin{align*}
a\\
b\\
c\\
d\\
e\tag{\stepcounter{equation}\theequation}\\
f\\
g\\
h\\
i
\end{align*}
\end{document}
Here is a small sample of numbering equations.
\documentclass[12pt]{article}
\usepackage{amsmath}
\begin{document}
\begin{align} % numbers equations automatically
x &= (1-x) + 2x \\ % \\ ends the line
&= (x+y) - y \nonumber \\ % \nonumber removes the equation number
&= \frac{x}{2} + \frac{x}{2} % last line does not have \\
\end{align}
\begin{align*} % use of * removes all numbers in this block
x &= (2x + 5) - (x+5) \\
&= yx - (y-1) x
\end{align*}
\end{document}
This sample produces
Best Answer
If you want to have each equation centered rather than aligned on some specific point (such as the first
=symbol), you should use agatheredenvironment instead of analignedenvironment.