Math & Science ⇒ Multiline Equation with Alignment

[mbaqar]

Hi
I have to compose a very long equation keeping the alignment intact. I have tried a number of options but in vain. Please examine the following code:

Code: Select all

\begin{equation}
\begin{split}
x &= a + b + c + d &\\
   &= e + f + g + h + i +j + k + l + m + n + o &\\ p + q + r + s  + t \\
   &= u 
\end{split}
\end{equation}

I want to set this equation in a manner that "p" appears below "e". I have been using different hacks but nothing doing.

Please help.

[Stefan Kottwitz]

You can nest split or aligned environments, or use an alignat environment for aligning at several places, but a quick easy way is to have an invisible equal sign:

Code: Select all

\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{equation}
\begin{split}
x &= a + b + c + d \\
  &= e + f + g + h + i +j + k + l + m + n + o + {}\\
  &\mathrel{\hphantom{=}} p + q + r + s  + t \\
  &= u
\end{split}
\end{equation}
\end{document}

Stefan

[mbaqar]

Thanks a lot Stefan. I am grateful.