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%\usepackage[dvips]{graphics}
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%\usepackage{graphicx}
%\usepackage{latexsym}
%\usepackage{amsfonts}
%\usepackage{amssymb}
%\usepackage{amsthm}
%\input psfig.tex

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\newcommand{\be}{\begin{eqnarray}}
\newcommand{\ee}{\end{eqnarray}}

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\def\title #1{\begin{center}{\Large {\bf #1}}\end{center}}

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\begin{document}

\vspace*{4mm}


\title{\LaTeX\, Examples: \\ Formula}
 \vspace*{10mm}

As stated earlier, mathematical statements, equations and formulas
can be entered in the text. This is done using by wrapping dollar
signs (\$) around the statement, such as \verb+$x-2\leq-8$+
$\Rightarrow$ $x-2\leq-8$.

Mathematical statements, equations and formulas can also be written
with the either the ``equation'' or ``eqnarray'' commands. \be
    \sum_{i=1}^{n}i & = & \frac{n(n+1)}{2} \nonumber \\
    \sum_{i=1}^{n}i^{2} & = & \frac{n(n+1)(2n+1)}{6}
    \label{eq:pt2}
\ee
Note that we labeled the second part of the last
question as (\ref{eq:pt2}).



\end{document}