main.tex

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\DTMsetdatestyle{mmddyyyy}

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\title[Beamer Blackboard Theme]{Simple Proof}
\author{Luis R. Guzman, Jr.}
\date[\today]{{\footnotesize \today}}
\institute{{\footnotesize University of West Florida}}

\begin{document}

% set handwritten font, necessary packages are loaded in beamerthemeblackboard.sty
\ECFAugie

\begin{frame}[t]
    \maketitle
\end{frame}

\begin{frame}[t]
    \frametitle{\Large Outline of Talk}
    \begin{itemize}
        \item Point one
        \item Point two
        \item ...
    \end{itemize}
\end{frame}

\begin{frame}[t]
{1 = 0.999...}
Proof.
Set $x = 0.999\ldots$. Then
\begin{table}
\centering
\begin{tabular}{r r@{.} l}
 & $10x$ $=$ $9$&$999\ldots$\\
$-$&  $x$ $=$ $0$&$999\ldots$\\\hline
 &  $9x$ $=$ $9$&$000\ldots$
\end{tabular}
\end{table}
Thus $x = 1.000\dots$ $\Box$
\end{frame}
\end{document}