%%
%% Ein Beispiel der DANTE-Edition
%% Mathematiksatz mit LaTeX
%% 3. Auflage
%% Beispiel 06-03-3 auf Seite 97.
%% Copyright (C) 2018 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
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\documentclass[10pt]{screxa}
\pagestyle{empty}
\setlength\textwidth{352.81416pt}
\AtBeginDocument{\setlength\parindent{0pt}}
%StartShownPreambleCommands
\usepackage{amsmath}
%StopShownPreambleCommands
\begin{document}
\begin{gather*}
A = \lim _{n\rightarrow \infty }\Delta x\left( a^{2}+\left( a^{2}+2a\Delta x+\left(
\Delta x\right) ^{2}\right)\right.\\
+\left( a^{2}+2\cdot 2a\Delta x+2^{2}\left( \Delta x\right) ^{2}\right)
+\left( a^{2}+2\cdot 3a\Delta x+3^{2}\left( \Delta x\right) ^{2}\right)\\
+ \ldots\\
\left.+\left( a^{2}+2\cdot (n-1)a\Delta x +(n-1)^{2}
\left( \Delta x\right) ^{2}\right) \right)\\
= \frac{1}{3}\left( b^{3}-a^{3}\right)
\end{gather*}
\end{document}
