&nbsp;trigexpand&nbsp;(%);
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3
(%o11)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;cos&nbsp;(u)&nbsp;(cos(u)&nbsp;sin(v)&nbsp;+&nbsp;sin(u)&nbsp;cos(v))

</pre>
The function <tt>trigreduce</tt>, on the other hand, converts an
expression into a form which is a sum of terms, each of which contains
only a single <tt>sin</tt> or <tt>cos</tt>:

<pre>
(%i12)&nbsp;trigreduce&nbsp;(%o10);
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&n