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\section{Evaluate At}
\[  a |_\infty \]
\[ a b |_{a=0} c d |_{c=0} e \]
\subsection{Conditional (probability)}
\[ a|b \]
\[ b_{a|b} \]
\section{Absolute values}
\[  |a| \]
\[ 2|ab| \] % absolute value monomial
\[ ||a|| \]
\[ || x || a || y || \] % 2-norms monomial
\[  |a |_\infty \]
\[  |a + b| \]
\[  |a - |b|| \]
\[ \int |x| dx \]
\[ \exp (-p(\ln|t|+i\sin t)) \]
\section{Failures w/o Backtracking}
\[  ||a| - |b|| \]
\[ ||a|-b| \]
\[  |a | b |_\infty \]
% This one's too weird
%\[  |a b |_\infty c | \]
\section{Quantum Mechanics \& Sets}
See qm.tex and sets.tex
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