<?xml version="1.0"?>
<div class="add">

<b>let </b><font color="Maroon">n</font> be    <a href="subset_1.html#M1">Element</a> of  <a href="numbers.html#K5">NAT</a> ;<br/><b>let </b><font color="Maroon">x1</font> be    <a href="subset_1.html#M1">Element</a> of  <a href="euclid.html#K1">REAL</a> <font color="Maroon">n</font>, <font color="Maroon">x2</font> be    <a href="subset_1.html#M1">Element</a> of  <a href="euclid.html#K1">REAL</a> <font color="Maroon">n</font>, <font color="Maroon">x3</font> be    <a href="subset_1.html#M1">Element</a> of  <a href="euclid.html#K1">REAL</a> <font color="Maroon">n</font>;<br/>



<a NAME="E1:37"/><i><font color="Green">E41</font></i>: 
(  <a href="finseq_1.html#K3">len</a> <span class="p1">(<span class="default"><a href="euclid_4.html#K3" target="_self">Rn2Fin</a> <font color="Maroon">x1</font></span>)</span> <a href="hidden.html#R1">=</a> <font color="Maroon">n</font> &amp;  <a href="finseq_1.html#K3">len</a> <span class="p1">(<span class="default"><a href="euclid_4.html#K3" target="_self">Rn2Fin</a> <font color="Maroon">x2</font></span>)</span> <a href="hidden.html#R1">=</a> <font color="Maroon">n</font> &amp;  <a href="finseq_1.html#K3">len</a> <span class="p1">(<span class="default"><a href="euclid_4.html#K3" target="_self">Rn2Fin</a> <font color="Maroon">x3</font></span>)</span> <a href="hidden.html#R1">=</a> <font color="Maroon">n</font> )
 
<b>by </b><i/>;<br/>
<b>thus </b><a NAME="E2:37"/>
<span class="p1"><a href="euclid_4.html#K5" target="_self">|(</a><span class="default"><span class="p2">(<span class="default"><font color="Maroon">x1</font> <a href="euclid.html#K8">-</a> <font color="Maroon">x2</font></span>)</span>,<font color="Maroon">x3</font></span><a href="euclid_4.html#K5" target="_self">)|</a></span> <a href="hidden.html#R1">=</a> <span class="p1"><a href="euclid_4.html#K5" target="_self">|(</a><span class="default"><font color="Maroon">x1</font>,<font color="Maroon">x3</font></span><a href="euclid_4.html#K5" target="_self">)|</a></span> <a href="real_1.html#K5">-</a> <span class="p1"><a href="euclid_4.html#K5" target="_self">|(</a><span class="default"><font color="Maroon">x2</font>,<font color="Maroon">x3</font></span><a href="euclid_4.html#K5" target="_self">)|</a></span>
 <b>by </b><i>, <a class="ref" href="euclid_2.html#T25">EUCLID_2:25</a></i>;<br/>


</div>
