$\displaystyle \frac{\mathit{a}^b}{\xi}$ $\textstyle =$ $\displaystyle \mathtt{\acute{e}}$(1)
$\displaystyle X$ $\textstyle =$ $\displaystyle Y$(2)
${x^i}\over{\tan y}$ $a \backslash{} b$ $\mathtt{math code} a < b$ $\underline{\mathtt{math \hbox{ code }}} \sum_{i}{\underline{\mathit{eff}}}$ $\sum_{i} f(x)^{2}$
$\displaystyle -- f(x) = {1 \over \sigma \sqrt{2\pi}}e^{-{1 \over 2}\left({x-\mu \over \sigma}\right)^2}
$