\section{Heat Equation}
\label{ch:heat_equation}

\subsection{Physical Derivation}
\label{sec:ch12_physical_derivation}

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\subsection{Separation of Variables}
\label{sec:ch12_separation_of_variables}

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\subsection{Dirichlet Boundary Conditions}
\label{sec:ch12_dirichlet}

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\subsection{Neumann Boundary Conditions}
\label{sec:ch12_neumann}

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\subsection{Steady-State Solution}
\label{sec:ch12_steady_state}

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\subsection{Source Terms}
\label{sec:ch12_source_terms}

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\subsection{Summary}
\label{sec:ch12_summary}

% Summary table at end of chapter
\begin{table}[htbp]
\centering
\caption{Chapter Summary}
\label{tab:ch12_summary}
\begin{tabular}{l l}
\toprule
\textbf{Concept} & \textbf{Key Formula/Method} \\
\midrule
TBD & TBD \\
\bottomrule
\end{tabular}
\end{table}