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<b>let </b><font color="Maroon" title="c1">x</font>, <font color="Maroon" title="c2">x1</font>, <font color="Maroon" title="c3">y1</font>, <font color="Maroon" title="c4">z1</font> be   <a href="real_1.html#NM1" title="REAL_1:NM.1">Real</a>;<br/>







<a NAME="E1:10"/>
( <span class="p1"><a href="euclid_5.html#K4" title="EUCLID_5:func.4">|[</a><span class="default"><font color="Maroon" title="c2">x1</font>,<font color="Maroon" title="c3">y1</font>,<font color="Maroon" title="c4">z1</font></span><a href="euclid_5.html#K4" title="EUCLID_5:func.4">]|</a></span> <a href="euclid_5.html#K1" title="EUCLID_5:func.1">`1</a>  <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c2">x1</font> &amp; <span class="p1"><a href="euclid_5.html#K4" title="EUCLID_5:func.4">|[</a><span class="default"><font color="Maroon" title="c2">x1</font>,<font color="Maroon" title="c3">y1</font>,<font color="Maroon" title="c4">z1</font></span><a href="euclid_5.html#K4" title="EUCLID_5:func.4">]|</a></span> <a href="euclid_5.html#K2" title="EUCLID_5:func.2">`2</a>  <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">y1</font> &amp; <span class="p1"><a href="euclid_5.html#K4" title="EUCLID_5:func.4">|[</a><span class="default"><font color="Maroon" title="c2">x1</font>,<font color="Maroon" title="c3">y1</font>,<font color="Maroon" title="c4">z1</font></span><a href="euclid_5.html#K4" title="EUCLID_5:func.4">]|</a></span> <a href="euclid_5.html#K3" title="EUCLID_5:func.3">`3</a>  <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c4">z1</font> )
 
<b>by </b><i><a class="ref" href="euclid_5.html#T2" target="_self" title="EUCLID_5:th.2">Th2</a></i>;<br/>
<b>hence </b><a NAME="E2:10"/>
<font color="Maroon" title="c1">x</font> <a href="euclid.html#K18" title="EUCLID:func.18">*</a> <span class="p1"><a href="euclid_5.html#K4" title="EUCLID_5:func.4">|[</a><span class="default"><font color="Maroon" title="c2">x1</font>,<font color="Maroon" title="c3">y1</font>,<font color="Maroon" title="c4">z1</font></span><a href="euclid_5.html#K4" title="EUCLID_5:func.4">]|</a></span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"><a href="euclid_5.html#K4" title="EUCLID_5:func.4">|[</a><span class="default"><span class="p2">(<span class="default"><font color="Maroon" title="c1">x</font> <a href="binop_2.html#K11" title="BINOP_2:func.11">*</a> <font color="Maroon" title="c2">x1</font></span>)</span>,<span class="p2">(<span class="default"><font color="Maroon" title="c1">x</font> <a href="binop_2.html#K11" title="BINOP_2:func.11">*</a> <font color="Maroon" title="c3">y1</font></span>)</span>,<span class="p2">(<span class="default"><font color="Maroon" title="c1">x</font> <a href="binop_2.html#K11" title="BINOP_2:func.11">*</a> <font color="Maroon" title="c4">z1</font></span>)</span></span><a href="euclid_5.html#K4" title="EUCLID_5:func.4">]|</a></span>
 <b>by </b><i><a class="ref" href="euclid_5.html#T7" target="_self" title="EUCLID_5:th.7">Th7</a></i>;<br/>


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