%% 
%%  Example 02-02-10 
%%  Copyright (C) 2016 Herbert Voss
%% 
%% ==== 
% Show page(s) 1
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\documentclass[]{screxa}
\pagestyle{empty}
\setlength\textwidth{328.62788pt}
\setlength\parindent{0pt}
%StartShownPreambleCommands
\usepackage{amsmath}
%StopShownPreambleCommands
\begin{document}
\begin{multline}
\frac{\mathrm{d}G_\infty}{\mathrm{d}n} =
      \frac{1}{\left( {1-e^{-pn}} \right)^2 }\cdot
      \left\{\vphantom{\frac{Q}{p}}% >>>> to get the correct height <<<<<
      \left[ 1-e^{-pn} \right] \left[ Q \left( n \right) - pR
      \left( n \right) + R'\left( n \right) \right]e^{-pn}\right.\\
    - \left.\left[-\frac{Q \left( n \right) e^{-pn}}{p} +
    \frac{Q \left( 0 \right)}{p} + R \left( n \right) e^{-pn}
    - A\right] pe^{-pn}\right\} = 0
\end{multline}
\end{document}
