--- a/slides/slides05.tex	Wed Oct 25 00:05:59 2017 +0100
+++ b/slides/slides05.tex	Tue Oct 31 21:32:12 2017 +0000
@@ -274,7 +274,7 @@
 \bl{$Rec(x,v)$}\medskip
 
 \item \bl{$nullable(x:r) \dn nullable(r)$}
-\item \bl{$der\,c\,(x:r) \dn (x:der\,c\,r)$}
+\item \bl{$der\,c\,(x:r) \dn der\,c\,r$}
 \item \bl{$mkeps(x:r) \dn Rec(x, mkeps(r))$}
 \item \bl{$inj\,(x:r)\,c\,v \dn Rec(x, inj\,r\,c\,v)$}
 \end{itemize}\bigskip\bigskip
@@ -709,15 +709,15 @@
 \frametitle{Parse Trees}
 \mbox{}\\[-16mm]
 
-\bl{\begin{plstx}: \meta{E} ::= \meta{F} | \meta{F} \cdot * \cdot \meta{F}\\
-: \meta{F} ::= \meta{T} | \meta{T} \cdot + \cdot \meta{T} | \meta{T} \cdot - \cdot \meta{T}\\
-: \meta{T} ::= num\_token | ( \cdot \meta{E} \cdot )\\
+\bl{\begin{plstx}: \meta{E} ::= \meta{F} | \meta{T} \cdot + \cdot \meta{E} |  \meta{T} \cdot - \cdot \meta{E}\\
+: \meta{T} ::= \meta{F} | \meta{F} \cdot * \cdot \meta{T}\\
+: \meta{F} ::= num\_token | ( \cdot \meta{E} \cdot )\\
 \end{plstx}}
 
 \begin{center}\small
 \begin{tikzpicture}[level distance=8mm, blue]
   \node {$\meta{E}$}
-    child {node {$\meta{F}$} 
+    child {node {$\meta{T}$} 
      child {node {$\meta{T}$} 
                  child {node {(\,$\meta{E}$\,)}
                             child {node{$\meta{F}$ *{} $\meta{F}$}