How to extend long equations across two columns in LaTeX
Code
$\TeX$ In the document, the cuted package, true to its name, allows long equations to be cut (two cut) and typeset spanning both columns.
\begin{strip}, \end{strip}
\documentclass[twocolumn]{article}
\usepackage{amsmath}
\usepackage{lipsum}
\usepackage{cuted}
\begin{document}
\title{Two-column Document with Wide Equation}
\author{Daesick Ryu}
\maketitle
\section{Introduction}
\lipsum[1]
\section{Main Content}
\lipsum[2]
\begin{strip}
\begin{equation}
E = mc^2 + \frac{1}{2}mv^2 + \int_{0}^{\infty} \frac{\sin(x)}{x} \, dx + \sum_{n=1}^{\infty} \frac{1}{n^2} + u_{xx} + u u_{y} + x^{6} y + \tanh{xy} + \sum_{n \in \mathbf{Z}} \gamma(n)
\end{equation}
\end{strip}
\lipsum[3-4]
\end{document}
Here, the placeholder text was generated using the lipsum package.