
diff -r 70c307641d05 -r 1e4da6d2490c hws/hw03.tex
--- a/hws/hw03.tex	Mon Sep 22 13:42:14 2014 +0100
+++ b/hws/hw03.tex	Fri Sep 26 14:06:55 2014 +0100
@@ -11,34 +11,41 @@
 \begin{enumerate}
 \item What is a regular language?
 
-\item Assume you have an alphabet consisting of the letters $a$, $b$ and $c$ only.
-(1) Find a regular expression that recognises the two strings $ab$ and $ac$. (2)
-Find a regular expression that matches all strings \emph{except} these two strings.
-Note, you can only use regular expressions of the form 
+\item Assume you have an alphabet consisting of the letters
+      $a$, $b$ and $c$ only. (1) Find a regular expression
+      that recognises the two strings $ab$ and $ac$. (2) Find
+      a regular expression that matches all strings
+      \emph{except} these two strings. Note, you can only use
+      regular expressions of the form 
+      
+      \begin{center} $r ::=
+      \varnothing \;|\; \epsilon \;|\; c \;|\; r_1 + r_2 \;|\;
+      r_1 \cdot r_2 \;|\; r^*$ 
+      \end{center}
+
+\item Define the function \textit{zeroable} which takes a
+      regular expression as argument and returns a boolean.
+      The function should satisfy the following property:
+
 \begin{center}
-$r ::= \varnothing \;|\; \epsilon \;|\; c  \;|\; r_1 + r_2  \;|\; r_1 \cdot r_2 \;|\; r^*$
-\end{center}
-
-\item Define the function $zeroable$ which takes a regular expression as argument
-and returns a boolean. The 
-function should satisfy the following property:
-\begin{center}
-$zeroable(r)$ \;if and only if\; $L(r) = \varnothing$
+$\textit{zeroable(r)} \;\text{if and only if}\; L(r) = \varnothing$
 \end{center}
 
 \item Define the tokens and regular expressions for a language
-consisting of numbers, left-parenthesis (, right-parenthesis ),
-identifiers and the operations $+$, $-$ and $*$. Can the following strings 
-in this language be lexed?
+      consisting of numbers, left-parenthesis $($,
+      right-parenthesis $)$, identifiers and the operations $+$,
+      $-$ and $*$. Can the following strings in this language
+      be lexed?
 
 \begin{itemize}
-\item \texttt{"}$(a + 3) * b$\texttt{"}
-\item \texttt{"}$)()++ -33$\texttt{"}
-\item \texttt{"}$(a / 3) * 3$\texttt{"}
+  \item $(a + 3) * b$
+  \item $)()++ -33$
+  \item $(a / 3) * 3$
 \end{itemize}
 
+In case they can, can you give the corresponding token
+sequences.
 
-In case they can, can you give the corresponding token sequences.
 \end{enumerate}
 
 




