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%%  An UIT Edition example
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%%  Example 04-08-6 on page 53.
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%%  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.
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%% ==== 
% Show page(s) 1
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\documentclass[]{exaarticle}
\pagestyle{empty}
\setlength\textwidth{153.70511pt}
\AtBeginDocument{\setlength\parindent{0pt}}
\setcounter{equation}{27}
\renewcommand\theequation{4.\arabic{equation}}
\StartShownPreambleCommands

\StopShownPreambleCommands
\begin{document}
\begin{eqnarray}
f(x)                  &=&\hphantom{-}\frac{1}{x^2}\\
f^\prime(x)           &=&-\frac{2}{x^3}     \\[20pt]
\int f(x)\,\mathrm{d}x&=&-\frac{1}{x}
\end{eqnarray}
\end{document}