diff -r 10f02605a46a -r 35104ee14f87 handouts/notation.tex
--- a/handouts/notation.tex	Sun Sep 07 08:37:44 2014 +0100
+++ b/handouts/notation.tex	Sat Sep 13 04:30:25 2014 +0100
@@ -232,7 +232,7 @@
 
 \noindent Note the difference in the last two lines: the empty
 set behaves like $0$ for multiplication and the set $\{[]\}$
-like $1$ for multiplication.
+like $1$ for multiplication ($n * 1 = n$ and $n * 0 = 0$).
 
 Following the language concatenation, we can define a
 \defn{language power} operation as follows:
@@ -247,9 +247,10 @@
 set, but the set containing the empty string. So no matter
 what the set $A$ is, $A^0$ will always be $\{[]\}$. (There is
 another hint about a connection between the $@$-operation and
-multiplication: How is $x^n$ defined and what is $x^0$?)
+multiplication: How is $x^n$ defined recursively and what is
+$x^0$?)
 
-Next we can define the \defn{star operation} for languages: 
+Next we can define the \defn{star operation} for languages:
 $A^*$ is the union of all powers of $A$, or short
 
 \begin{equation}\label{star}