%% 
%%  An UIT Edition example
%% 
%%  Example 08-01-6 on page 151.
%% 
%%  Copyright (C) 2010 Herbert Voss
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 
%% 
%% ==== 
% Show page(s) 1
%% 
\documentclass[]{exaarticle}
\pagestyle{empty}
\setlength\textwidth{338.01643pt}
\AtBeginDocument{\setlength\parindent{0pt}}
\StartShownPreambleCommands
\newcommand*\diff{\mathop{}\!\mathrm{d}}
\StopShownPreambleCommands
\begin{document}
\[ f(x) = \int\frac{\sin x}{x}\diff x\  \fbox{\the\displayindent} \]
\[\displayindent=50pt
  f(x) = \int\frac{\sin x}{x}\diff x\  \fbox{\the\displayindent} \]
\[\displayindent=100pt
  f(x) = \int\frac{\sin x}{x}\diff x\  \fbox{\the\displayindent}\]
\end{document}
