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\title{Use Equation}
\author{Atsushi Sakaguchi}
\date{30 May, 2001}

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These are examples of EQUATION.  
\LaTeX can make equations easily.  
    \[ y = exp ( - \frac{x^{2}}{2 \sigma} ) \]
    \[ E = q / 4 \pi \epsilon_{0} r^{2}\]
    \[ rot H = J + \frac{\partial D}{\partial t} \]
    \[ I = \int_{a}^{b} x^{2} dx \]
In-line equation $ a = b^{2} $ is also possible.

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