--- a/slides/slides04.tex	Wed Oct 16 23:45:46 2019 +0100
+++ b/slides/slides04.tex	Thu Oct 17 13:41:30 2019 +0100
@@ -1,3 +1,4 @@
+% !TEX program = xelatex
 \documentclass[dvipsnames,14pt,t]{beamer}
 \usepackage{../slides}
 \usepackage{../graphics}
@@ -143,6 +144,53 @@
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \begin{frame}[c]
+\frametitle{Coursework}
+
+\begin{itemize}
+\item \bl{$\der\,c\,(r^+) \dn \der\,c (r\cdot r^*)$}\quad given
+that \bl{$r^+ \dn r\cdot r^*$}
+\end{itemize}\bigskip\pause
+
+\begin{center}
+\begin{tabular}{lcl}
+\bl{$\der\,c\,(r\cdot r^*)$} & \bl{$\dn$} & 
+\only<2-4>{if \bl{$nullable\,r$}}%
+\only<5>{\bl{$(\der\,c\,r)\cdot r^*$}}\\
+ & & 
+ \only<2>{then \bl{$(\der\,c\,r)\cdot r^* \,+\, \der\,c\,(r^*)$}}%
+ \only<3>{then \bl{$(\der\,c\,r)\cdot r^* \,+\, (\der\,c\,r)\cdot r^*$}}%
+ \only<4>{then \bl{$(\der\,c\,r)\cdot r^*$}}\\
+ & & \only<2-4>{else \bl{$(\der\,c\,r)\cdot r^*$}}
+\end{tabular}  
+\end{center}  
+\end{frame}
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+\begin{frame}[c]
+  \frametitle{Coursework (2)}
+  
+  \begin{itemize}
+  \item \bl{\texttt{CFUN(f: Char => Boolean)}}
+  \end{itemize}\medskip
+
+  \begin{center}
+  \begin{tabular}{l}
+  \bl{\texttt{CHAR(c: Char)}} \bl{$\dn$}\\
+     \quad\bl{\texttt{CFUN(\_ == c)}}\medskip\\
+  \bl{\texttt{RANGE(cs: Set[Char])}} \bl{$\dn$}\\
+     \quad\bl{\texttt{CFUN(cs.contains(\_))}}\medskip\\
+  \bl{\texttt{ALL}} \bl{$\dn$}\\
+     \quad\bl{\texttt{CFUN((c: Char) => true)}}\\
+  \end{tabular}  
+  \end{center}  
+\end{frame}
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
+  
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+\begin{frame}[c]
 \frametitle{Regexps and Automata}
 
 \begin{center}