# Problem with fraction and align environment - “&” symbol

I am new in LaTeX, thus I need your help.

I want to align the \leq symbol under the + symbol. The problem is that the + symbol is contained inside a fraction, therefore, the \begin{aligned}--\end{aligned} environment, does not allow me to insert the & symbol inside this certain fraction.

How can I achieve this without having any problems?

An example:

\displaystyle \begin{aligned} \sqrt{\frac{2x}{y **&+** z}}+\sqrt{\frac{2y}{z+x}}+\sqrt{\frac{2z}{x+y}}\\ &\leq 3. \end{aligned}


P.S I have searched the site but I haven't found anything similar with my problem. (maybe I am not searching, right?)

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Welcome to TeX.sx! – Kurt Dec 5 '12 at 20:17

I would recommend a different approach and that is to use an \hphantom to insert the appropriate amount of horizontal space:

## Notes:

• I used \hphantom instead of \phantom as I did not want the vertical size of \sqrt{{\frac{2x}{y **}}} to affect the second row.
• Alignment points located inside other terms such as \sqrt and frac are not usually this easy to do, and David's solution was quite clever in moving it outside and inserting a negative \hspace. I personally would never have thought of that as I tend to think of alignment form the left moving towards the right.

## Code:

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\displaystyle \begin{aligned} &\sqrt{\frac{2x}{y **+** z}}+\sqrt{\frac{2y}{z+x}}+\sqrt{\frac{2z}{x+y}}\\ &\hphantom{\sqrt{{\frac{2x}{y **}}}}\leq 3. \end{aligned}

\end{document}

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If you have some multline equation to typeset and you don't align globally by = or \leq, I would suggest you to try:

\begin{multline}
f/i/r/s/t + l/i/n/e
\\
\leq s/e/c/o/n/d + l/i/n/e
.\end{multline}


And surely you should use proper displayed equation and never ever do \displaystyle. The env multline is provided by the package amsmath and you do not put it inside another environment (it is similar to equation). As well, it has a starred variant multline* that suppresses the numbering. - @George, while the other two answers do what you asked, you should accept this one, you don't need alignment here. – David Carlisle Dec 5 '12 at 21:02 This is a seriously odd place to align, what mathematical meaning do you mean to convey by aligning the inequality with the + in the subterm? However: \documentclass{article} \usepackage{amsmath} \newlength\mlength \begin{document} \settowidth{\mlength}{+**z$}$\displaystyle \begin{aligned}
\sqrt{\frac{2x}{y **+** z}}&+\sqrt{\frac{2y}{z+x}}+\sqrt{\frac{2z}{x+y}}\\
&\hspace{-\mlength}\leq 3.
\end{aligned}\$

\end{document}

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Hello. Thank you for you quick response. Well, I have some big Inequality expressions, and when I align them to center I must break them in 2 lines. But there is a problem at this point, since they exceed the paper size. – George Dec 5 '12 at 20:10
Breaking into multiple lines is fine but aligning the <= with a + in a subterm makes no mathematical sense, the alignment is intended to align matching operators – David Carlisle Dec 5 '12 at 20:47