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<A NAME=LCOF>

<TITLE>LCOF</TITLE></A>
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<B>LCOF</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
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The <em>lcof</em> operator returns the leading coefficient of a given expression
 
with respect to a given variable. 
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syntax: </H3>
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<em>lcof</em>(&lt;expression&gt;,&lt;kernel&gt;) 
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&lt;expression&gt; is ordinarily a polynomial. If 
<A HREF=r37_0322.html>ratarg</A> is on, 
a rational expression may also be used, otherwise an error results. 
&lt;kernel&gt; must be a 
<A HREF=r37_0002.html>kernel</A>. 
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examples: </H3>
<P><PRE><TT>
lcof((x+2*y)**5,y); 

  32 


lcof((x + y*sin(x))**2 + cos(x)*sin(x)**2,sin(x));
			 


        2
  COS(X)  + Y 


lcof(x**2 + 3*x + 17,y); 

   2
  X  + 3*X + 17

</TT></PRE><P>If the kernel does not appear in the expression, <em>lcof</em> ret
urns the 
expression. 
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