\documentclass[minion]{homework}
\usepackage{cmacros}
\def\calB{\mathcal{B}}
\begin{document}
\doclabel{Math 617: Homework 5}
\docdate{Due: February 22, 2012}
\begin{aproblems}
\hproblem D \& M 3.37 

% \hproblem \solver{Will Mitchell}
% Let $X$ be an inner-product space.  
% Show that if $P:X\ra X$ 
% satisfies $P^2=P$ and $||P||=1$, then
% $P$ is the orthogonal projection onto $P(X)$.

\hproblem 
Let $X$ be a Hilbert space. If $E\subseteq X$ is
a subspace, show that $(E^\perp)^\perp$ is the smallest
closed subspace containing $E$.

\hproblem D \&M 3.51

\end{aproblems}
\end{document}