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\begin{document}

\homework{1}{September 6, 2013}{David Witmer}{dwitmer}{Jacob Bernoulli, Sim\'{e}on Denis Poisson}

{\Large \bf 1}
\begin{enumerate}[(a)]
\item
From class, recall that for a discrete random variable $X$ taking on values $x_1,x_2,\ldots$, the expected value of $X$ is 
\[
\E[X] = \sum_{i = 1}^{\infty} x_i p_X(x_i).
\]

\item
On the other hand, for a continuous random variable $X$, the expected value is
\[
\E[X] = \int_{-\infty}^{\infty} x f_X(x)\,dx.
\]

\end{enumerate}
\end{document}
