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<A NAME=GCD>

<TITLE>GCD</TITLE></A>
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<B>GCD</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
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The <em>gcd</em> operator returns the greatest common divisor of two 
polynomials. 
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syntax: </H3>
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<em>gcd</em>(&lt;expression&gt;,&lt;expression&gt;) 
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&lt;expression&gt; must be a polynomial (or integer), otherwise an error 
occurs. 
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examples: </H3>
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gcd(2*x**2 - 2*y**2,4*x + 4*y); 

  2*(X + Y) 


gcd(sin(x),x**2 + 1); 

  1  


gcd(765,68); 

  17

</TT></PRE><P>The operator <em>gcd</em> described here provides an explicit mean
s to find the 
gcd of two expressions. The switch <em>gcd</em> described below simplifies 
expressions by finding and canceling gcd's at every opportunity. When 
the switch 
<A HREF=r37_0286.html>ezgcd</A> is also on, gcd's are figured using the EZ GCD 
algorithm, which is usually faster. 
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