# How to break a equation with a single “summation symbol (\sum) ” common?

How to break an equation with a single summation symbol common ? I want to write the equation like the following in two line

$\sum [(a+b+c+.........+d) +(e+f+............+l]=0$


To break a formula into several columns, with a single “summation symbol” common, you could use (also) the enviroment split. See this MWE and you can also compare it with other answers. If you want increase the brackets ( or [, considering that they are on two different lines, you should use (for example) \bigl( or \bigr) to not have any errors. \documentclass[a4paper,12pt]{article}
\usepackage{amsmath,amssymb}

\begin{document}
\begin{equation}
\begin{split}
&\sum[(a+b+c+\dotsb+d)\\
& +(e+f+\dotsb+l)]=0
\end{split}
\end{equation}
\end{document}


## ADDEDUM after the comment of the user @M. A. SARKAR

As by your request I add you other alternatives where I increased the size of the square brackets with the appropriate commands. I hope I have understood your request.

\documentclass[a4paper,12pt]{article}
\usepackage{amsmath,amssymb}

\begin{document}
\begin{equation}
\begin{split}
&\sum\bigl[(a+b+c+\dotsb+d)\\
& +(e+f+\dotsb+l)\bigr]=0
\end{split}
\end{equation}

\begin{equation}
\begin{split}
&\sum\Bigl[(a+b+c+\dotsb+d)\\
& +(e+f+\dotsb+l)\Bigr]=0
\end{split}
\end{equation}

\begin{equation}
\begin{split}
&\sum\Biggl[(a+b+c+\dotsb+d)\\
& +(e+f+\dotsb+l)\Biggr]=0
\end{split}
\end{equation}

\end{document}

• How to use the latex code "\left[ \right]" in the above code in order to get large 3rd bracket? – M. A. SARKAR Nov 16 '19 at 18:18
• @M.A.SARKAR I have edit my answer with an addendum. – Sebastiano Nov 16 '19 at 23:06
• @M.A.SARKAR No, no, please. Can you give to the user bgleb the check green mark please? This is check is not mine. Just for justice. – Sebastiano Nov 17 '19 at 16:40

An alternative

\documentclass[twocolumn]{article}
\usepackage{mathtools}

\begin{document}
$\begin{multlined}[0.7\linewidth] \sum \bigl[(a+b+c+d) \\ + (e+f+g+h+i+j+k+l)\bigr] = 0 \end{multlined}$
\end{document} \usepackage{amsmath}
\begin{document}

\begin{align*}
&\sum (a+b+c+d \\
&+e+f+g+h+i+j+k+l)
\end{align*}

\end{document} • In your answer is missed \documentclas{...} ... – Zarko Nov 16 '19 at 9:52
• I would replace &\sum (a+b+c+d by \sum (&a+b+c+d and probably move also the + before the e directly after the d. – albert Nov 16 '19 at 10:03
• @Zarko This example will work with any \documentclass parameter, so there is not much point including that in the example. I have included the \begin{document} in order to show that it goes in the preamble. – bgleb Nov 16 '19 at 10:31
• @Teepeemm package is included in line 1 – bgleb Nov 18 '19 at 20:21