\documentclass{jarticle}
\title{\TeX\ Sample}
\author{Shun-ichi KURINO}
\date{2010/05/25}
\begin{document}
\maketitle
Hello, \TeX World.
We can use mathematical expression like as $\frac{\pi}{\sqrt{2}}$ in line.
More complex expression in paragraph.

\[
\int_{0}^{1}\frac{1}{\sqrt{1-x^2}}dx = \frac{1}{4}\pi
\]

You interest in \TeX\ don't you ?

\end{document}
