Turn off equation auto numbering in LaTeX

In this tutorial, I will show you how to turn off the equation auto numbering for a single equation or a set of equations in LaTeX.

Turn off numbering for single line equation

In order to turn off the equation numbering for a single-line equation you can use the \nonumber command provided by the amsmath package. You have to use this command at the end of the expression.

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\begin{center}
    \underline{Single line equation with equation number}
\end{center}
\begin{equation}
    x = a + 3^2 + (2+2)
\end{equation}
\begin{center}
    \underline{Single line equation without equation number}
\end{center}
\begin{equation}
    x = a + 3^2 + (2+2)\nonumber
\end{equation}

\end{document}

Output:

Also, you can use the equation* environment to get an unnumbered single-line equation.

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\begin{center}
    \underline{Single line equation with equation number}
\end{center}
\begin{equation}
    x = a + 3^2 + (2+2)
\end{equation}
\begin{center}
    \underline{Single line equation without equation number}
\end{center}
\begin{equation*}
    x = a + 3^2 + (2+2)
\end{equation*}

\end{document}

Output:

Turn off equation number for a set of equations

You can use the \nonumber command at the end of every expression and also with the environment like, \begin{align}\nonumber to turn off equation numbers for a set of equations, but I don’t recommend this.

A better method is, to use the align* environment to get an unnumbered equation for a set of equations. Don’t forget to load the amsmath package.

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\begin{center}
    \underline{Set of equations with equation number}
\end{center}
\begin{align}
     x &= a + 3^2 + (2 \times 2) \\
       &= a + 9 + 4 \\
       &= a + 13
\end{align}
\begin{center}
    \underline{Set of equations without equation number with \textbackslash\texttt{nonumber}}
\end{center}
\begin{align} \nonumber
     x &= a + 3^2 + (2 \times 2) \\ \nonumber
       &= a + 9 + 4 \\ \nonumber
       &= a + 13 \nonumber
\end{align}
\begin{center}
    \underline{Set of equations with equation number with \texttt{align*}}
\end{center}
\begin{align*}
     x &= a + 3^2 + (2 \times 2) \\
       &= a + 9 + 4 \\
       &= a + 13
\end{align*}

\end{document}

Output:

Set of equations with one equation number

To assign a set of equations with one equation number you can use the split environment inside the equation environment.

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\begin{center}
    \underline{Set of equations with one equation number}
\end{center}
\begin{equation}
\begin{split}
     x &= a + 3^2 + (2 \times 2) \\
       &= a + 9 + 4 \\
       &= a + 13
\end{split}
\end{equation}

\end{document}

Output: