Take the 2-minute tour ×
TeX - LaTeX Stack Exchange is a question and answer site for users of TeX, LaTeX, ConTeXt, and related typesetting systems. It's 100% free, no registration required.

How can I implement the alignment like in the following image?

https://docs.google.com/open?id=0B1kX_CbBVoMtSDQ0bVFaZ1JURS1lbXFPandBS01CZw

Because the usual \begin{align*} and \end{align*} command can not work, so I hope you can help me!

Thanks! Wait for your elegant codes or solutions...

share|improve this question
    
Hi user9701, welcome to TeX.sx! Maybe you could change the question title into something a little more meaningful, so others facing the same issue can come across this thread more easily. –  Jake Apr 2 '12 at 17:46
add comment

3 Answers

Actually, you can use align*:

\begin{align*}
   &A(x) \\
={}&B(x) \\
={}&C(x)
\end{align*}

The {} after = is necessary to ensure correct spacing (which is better than what's obtained with eqnarray).

In normal cases one puts the relation symbol after the &, but in this case this would require the cumbersome \mathrel{\phantom{=}} A(x) as in Marco Daniel's answer (which is correct, nonetheless).

One should simply remind that align produces blocks of rl columns, without any space between them (and generous space between blocks). However, it takes special precautions so that a relation symbol after & has the correct spaces, but doesn't before the &. Here the easier solution is to put an empty subformula after the =, which produces the correct space.

Generally the relation symbol goes after the &, which is a rule to be broken only in a few special cases.

share|improve this answer
add comment

One of the golden rules of amsmath is to use the separator before any relation. To suppress the first relation without using the space you can use the commands \mathrel in combination with \phantom:

\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{align*}
&\mathrel{\phantom{=}} A(x) \\
&=B(x) \\
&=C(x)
\end{align*}
\end{document}

share|improve this answer
add comment

Judging from the spacing it looks like a regular old eqnarray (which should never be used anyway).

share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.