## LaTeX forum ⇒ General ⇒ Limiter Topic is solved

LaTeX specific issues not fitting into one of the other forums of this category.
rodrigue
Posts: 9
Joined: Fri Dec 27, 2019 9:18 am

### Limiter

Hi all,

I'm new in this forum I I'm facing an error in latex since this morning when writhing an equation. I used a limiter (In french we call it délimiteur) in order to group it. The code is the following:

\documentclass[a4paper, 12pt]{report}
\usepackage[utf8]{inputenc}
\usepackage{lmodern}
\usepackage[T1]{fontenc}
\usepackage[french]{babel}
\usepackage{lmodern}
\usepackage{array}
\usepackage{rotating}
\usepackage{graphicx}

\usepackage{amsmath,amssymb,amsfonts}
\usepackage{amsthm}
\usepackage[a4paper]{geometry}

\begin{document}

\begin{split}
\frac{\partial D_j}{\partial Pd_j} = PC_jQ_j(1-\alpha_j)^{\sigma_j}
\left\lbrace -\sigma_j Pd_j^{-\sigma_j - 1}
\left[\alpha_j^{\sigma_j}Pm_j^{1-\sigma_j}+(1-\alpha_j)^{\sigma_j} Pd_j^{1-\sigma_j} \right]^{-1} & \\
-Pd_j^{-\sigma_j}(1-\sigma_j)Pd_j^{-\sigma_j}(1-\alpha_j)^{\sigma_j}
\left[\alpha_j^{\sigma_j}Pm_j^{1-\sigma_j}+(1-\alpha_j)^{\sigma_j} Pd_j^{1-\sigma_j} \right]^{-2} \right\rbrace
\end{split}

\end{document}

Now when I compile the code, I get the error messages telling me that I've not closed a bracket.

The probem occurs specifically in \left\lbrace and \right\rbrace. The first one that is \left\lbrace is working well but the second one \right\rbrace is not working. I don't understand what's wrong with my code.

Can someone tell me what to do?

Also look the attachment

delimiteur.tex

rais
Posts: 268
Joined: Sun Nov 16, 2014 8:51 pm
Hi,
each \left command must be accompanied by a matching \right command within the same line (and group).
Use \right. just before the & sign of the first line and
\left. at the beginning of the second line.

KR
Rainer

rodrigue
Posts: 9
Joined: Fri Dec 27, 2019 9:18 am
Hi Rainer