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<head><title>gcd -- greatest common divisor</title>
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<div><h1>gcd -- greatest common divisor</h1>
<div class="single"><h2>Synopsis</h2>
<ul><li><div class="list"><dl class="element"><dt class="heading">Usage: </dt><dd class="value"><div><tt>gcd(x,y,...)</tt></div>
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<li><div class="single">Inputs:<ul><li><span><tt>x</tt>, <span>an <a href="___Z__Z.html">integer</a></span></span></li>
<li><span>, or </span></li>
<li><span><span>a <a href="___Q__Q.html">rational number</a></span></span></li>
<li><span>, or </span></li>
<li><span><span>a <a href="___Ring__Element.html">ring element</a></span></span></li>
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<li><div class="single">Outputs:<ul><li><span><span>an <a href="___Z__Z.html">integer</a></span>, , or <span>a <a href="___Q__Q.html">rational number</a></span>, or <span>a <a href="___Ring__Element.html">ring element</a></span>, the greatest commond divisor of the arguments</span></li>
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<div class="single"><h2>Description</h2>
<div><table class="examples"><tr><td><pre>i1 : gcd(12,8,48)
o1 = 4</pre>
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<tr><td><pre>i2 : R = QQ[x,y,z];</pre>
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<tr><td><pre>i3 : gcd(x^2*y,x*y^3^6)
o3 = x*y
o3 : R</pre>
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<tr><td><pre>i4 : gcd(x^36-1,x^24-1)
12
o4 = x - 1
o4 : R</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="_gcd__Coefficients.html" title="gcd with coefficients">gcdCoefficients</a> -- gcd with coefficients</span></li>
<li><span><a href="_lcm.html" title="least common multiple">lcm</a> -- least common multiple</span></li>
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<div class="waystouse"><h2>Ways to use <tt>gcd</tt> :</h2>
<ul><li>gcd(List)</li>
<li>gcd(QQ,QQ)</li>
<li>gcd(QQ,ZZ)</li>
<li>gcd(RingElement,RingElement)</li>
<li>gcd(RingElement,ZZ)</li>
<li>gcd(Sequence)</li>
<li>gcd(ZZ,QQ)</li>
<li>gcd(ZZ,RingElement)</li>
<li>gcd(ZZ,ZZ)</li>
</ul>
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