How can I typeset a brace on the right-hand side of two equations?

Question

How to obtein this on latex?

Thank you.

Answer 1

Here are two methods for creating the output you're interested in. One involves the use of an array environment, and the other that of an rcases environment. The latter method requires less typing; however, it does require you to load the mathtools package -- which you may be doing anyway. Aside: If you use drcases instead of dcases, you could omit the two \displaystyle directives, for further savings in terms of typing effort.

\documentclass{article}
\usepackage{mathtools} % for 'rcases' environment
\setlength\textwidth{3in} % just for this example
\begin{document}
With \texttt{array} environment:

\[ 
\left.\begin{array}{ll}
  \displaystyle \int_\Omega f L(g)\,dx\\[2ex]
  \displaystyle \int_\Omega g L(f)\,dx
\end{array}\right\}
\]

\bigskip
With \texttt{rcases} environment:

\[
\begin{rcases}
  \displaystyle \int_\Omega f L(g)\,dx\\
  \displaystyle \int_\Omega g L(f)\,dx
\end{rcases}
\]
 \end{document}