Add the \preimage macro.

[mjotex.git] / examples.tex

diff --git a/examples.tex b/examples.tex
index 98ddfd550b08ea4fd78301eb47c0aea19cb8de7a..e0ffcb97a11ce5a97a2e837e7c994fd19714e1ae 100644 (file)
--- a/examples.tex
+++ b/examples.tex
@@ -28,7 +28,8 @@
   \begin{section}{Arrow}
     The identity operator on $V$ is $\identity{V}$. The composition of
     $f$ and $g$ is $\compose{f}{g}$. The inverse of $f$ is
-    $\inverse{f}$.
+    $\inverse{f}$. If $f$ is a function and $A$ is a subset of its
+    domain, then the preimage under $f$ of $A$ is $\preimage{f}{A}$.
   \end{section}
 
   \begin{section}{Common}