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 \hyphenation{time-de-pen-dent Schro dinger}
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\begin{center}
\textbf{\large A First Look at  \LaTeX}\end{center}

To learn \LaTeX\, a good place to start is with the sample \LaTeX\, file in \textit{Guide to \LaTeX} by Helmut Kopka and Patrick Daly.\footnote{The pdf file of this book is available on the Math 129 homepage.}

Below are some common commands for typesetting mathematical expressions:
\begin{enumerate}
\item Here is an formula written in-line: $H\psi=E\psi$.  Here is the same formula displayed
\[ H\psi = E \psi \]
Again, the same formula but this time with an equation number
\begin{equation}
H \psi = E\psi \label{SchEqn} 
\end{equation}
We can now refer to this equation (\ref{SchEqn}).
\item
Integrals are easy to write
\[ \int_0^\infty e^{-x^2}\, dx = \frac{\sqrt{\pi}}{2}. \]
\item Here is an example of a several equations in a multiline display
\begin{eqnarray}
A&=&B+1\label{AB}\\
C&=&D+\pi\label{CD}\nonumber\\
\Lambda&=&\frac{A}{B}+7\label{7}
\end{eqnarray}
If you don't want the equation numbers you use the \verb=\begin{eqnarray*}= and \verb=\end{eqnarray*}= commands.  You need to use the \verb=\label{}= command in the
eqnarray environment to refer back to the equation, e.g.\ (\ref{7}).  Note that the middle equation does not have an equation number.  This is because it was suppressed with
the \verb=\nonumber= command.
\item One more example:
\[ u(r,\theta)=\sum_{m=-\infty}^\infty a_m r^{\vert m\vert} e^{im\theta}\]
\end{enumerate}
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