s, <tt>[b1, b2, ..., bm]</tt>.</dd>
 <dt><b><tt>num(a)</tt></b></dt>
	<dd> Gives the numerator of <tt>a</tt>.</dd>
 <dt><b><tt>ode2(a,b,c)</tt></b></dt>
	<dd> Attempts to solve the first- or second-order
  ordinary differential equation <tt>a</tt> for <tt>b</tt> as a function of
  <tt>c</tt>.</dd>
 <dt><b><tt>part(a,b1,b2,...,bn)</tt></b></dt>
	<dd> First takes the <tt>b1</tt>th part
  of <tt>a</tt>, then the <tt>b2</tt>th part of that, and so on.</dd>
 <dt><b><tt>playback(a)</tt></b></dt>
	<dd> Displays th