diff --git a/Tutorials/T04-A2Example/slides/T4.tex b/Tutorials/T04-A2Example/slides/T4.tex
index 8abf50f49a4de2f735946bc046b457b2bc16c37c..6094c23ff46f815c39a1cc31921b4d7b1a8dc11e 100644
--- a/Tutorials/T04-A2Example/slides/T4.tex
+++ b/Tutorials/T04-A2Example/slides/T4.tex
@@ -414,11 +414,11 @@ init & pointT,pointT,pointT&TriangleADT & ~\\
 \hline
 sides & & &~\\
 \hline
-inequality theorem & ~ & boolean & LINE~\\
+inequality\char`_theorem & ~ & boolean & LINE~\\
 \hline
-perimeter of triangle & & real  & LINE ~\\
+perimeter\char`_of\char`_triangle & & real  & LINE ~\\
 \hline
-area of triangle &  & real & LINE ~\\
+area\char`_of\char`_triangle &  & real & LINE ~\\
 \hline
 \end{tabular}
 
@@ -480,10 +480,10 @@ init($p1, p2, p3$):
 \begin {frame}
 \noindent inequality theorem():
 \begin{itemize}
-\item output: $$out := \mathrm {(self.AB +self.AC > self.BC,and, self.AB+self.BC }$$
-	     $$ \mathrm {> self.AC, and,  self.AC+self.BC >self.AB)}$$
+\item output: $$out := \mathrm {(self.AB +self.AC > self.BC\quad and \quad self.AB+self.BC }$$
+	     $$ \mathrm {> self.AC\quad and\quad self.AC+self.BC >self.AB)}$$
 \item exception: 
-\\ ex := (self.a.xcoord()==self.b.xcoord() ==self.c.xcoord() or 
+\\ ex := ((self.a.xcoord()==self.b.xcoord() ==self.c.xcoord() or 
 \\ self.a.ycoord()==self.b.ycoord() ==self.c.ycoord()) $\Rightarrow \mbox{LINE})$
 \end{itemize}
 
@@ -499,7 +499,7 @@ init($p1, p2, p3$):
 \begin{itemize}
 \item output: $$out := \mathrm{self.AB+self.AC+self.BC}$$
 \item exception: 
-\\ ex := (self.a.xcoord()==self.b.xcoord() ==self.c.xcoord() or 
+\\ ex := ((self.a.xcoord()==self.b.xcoord() ==self.c.xcoord() or 
 \\ self.a.ycoord()==self.b.ycoord() ==self.c.ycoord()) $\Rightarrow \mbox{LINE})$
 
 \end{itemize}
@@ -507,7 +507,7 @@ init($p1, p2, p3$):
 \begin{itemize}
 \item  output : $$out :=\mathit {\sqrt[2]{P/2(P/2-self.AB)(P/2-self.AC)(P/2-self.BC)}}$$
 \item exception: 
-\\ ex := (self.a.xcoord()==self.b.xcoord() ==self.c.xcoord() or 
+\\ ex := ((self.a.xcoord()==self.b.xcoord() ==self.c.xcoord() or 
 \\ self.a.ycoord()==self.b.ycoord() ==self.c.ycoord()) $\Rightarrow \mbox{LINE})$
 \end{itemize}