alignequations
I am new to Latex 😉
I split my equation like this:
\begin{equation}
\begin{split}
\tilde{m}=P\tilde{M} \\
\quad = K(R^1R^2R^3t) \begin{pmatrix} X \\ Y \\ 0 \\ 1 \end{pmatrix} \\
\quad= K(R^1R^2t)\begin{pmatrix} X \\ Y \\ 1 \end{pmatrix} \\
\quad= H \begin{pmatrix} X \\ Y \\ 1 \end{pmatrix}
\end{split}
\end{equation}
which gives me this:
but, actually, I want it to be aligned like this:
How do I align them so it looks like the right side is always aligned?
Thanks
Use the ={}& trick:
\documentclass{article}
\usepackage{amssymb}
\usepackage{amsmath}
\usepackage[mathscr]{euscript}
\usepackage{mathtools}
\usepackage{graphicx}
\usepackage{caption}
\usepackage{chngcntr}
\usepackage{apptools}
\usepackage{amsthm}
\usepackage{hyperref}
\newcommand{\diff}{\mathop{}\!d}
\begin{document}
\begin{equation*}
\begin{aligned}
\frac{\partial E(\mu,\sigma,\theta,\beta)}{\partial \beta}
={}& \int\limits_\Omega \sum_{i=1}^N \frac{\partial r_i(x)}{\partial \beta}\diff x \\
={}& -\int\limits_\Omega \sum_{i=1}^N \left( \frac{( \mu-\sigma- \theta)}{\sigma_i}\right)\diff x
-\int\limits_\Omega \sum_{i=1}^N \left( \frac{( \mu-\sigma- \theta)}{\sigma_i}\right)\diff x\\
& -\int\limits_\Omega \sum_{i=1}^N \left( \frac{( \mu-\sigma- \theta)}{\sigma_i}\right)\diff x
-\int\limits_\Omega \sum_{i=1}^N \left( \frac{( \mu-\sigma- \theta)}{\sigma_i}\right)\diff x
\end{aligned}
\end{equation*}
\end{document}
Note how I defined a macro for the differential symbol and used \int\limits in order to push the Omega below the integral symbol, which is customary in this case.
Note that hyperref should be loaded last among the packages you have.
You can make use of mathtools' multlined environment:
\documentclass{article}
\usepackage{amsmath,mathtools}
\begin{document}
\[
\begin{split}
x &= a + a \\
&= b + b + b + b \\
&= \!\begin{multlined}[t]
c + c + c + c + c + c + c + c + c + c + c + c \\
+ c + c + c + c + c + c + c + c + c + c
\end{multlined}
\end{split}
\]
\end{document}
Note: the \! before the environment is to get correct spacing between = and c.
It's also possible to specify the total width of the two lines (from left margin at first line to right margin at last line) as an optional argument to multlined:
\documentclass{article}
\usepackage{amsmath,mathtools}
\begin{document}
\[
\begin{split}
x &= a + a \\
&= b + b + b + b \\
&= \!\begin{multlined}[t][10cm]
c + c + c + c + c + c + c + c + c + c + c + c \\
+ c + c + c + c + c + c + c + c + c + c
\end{multlined}
\end{split}
\]
\end{document}
If you want the two lines right aligned, you can set the mathtools key firstline-afterskip to 0pt, either globally or locally:
\documentclass[border=5pt,preview]{standalone}
\usepackage{amsmath,mathtools}
\begin{document}
\mathtoolsset{firstline-afterskip=0pt}
\[
\begin{split}
x &= a + a \\
&= b + b + b + b \\
&= \!\begin{multlined}[t]
c + c + c + c + c + c + c + c + c + c + c + c \\
+ c + c + c + c + c + c + c + c + c + c
\end{multlined}
\end{split}
\]
\end{document}
Best Answer
You just need to set an ampersand as alignment marker before the equal sign: