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<b>let </b><font color="Maroon">c<sub>1</sub></font>, <font color="Maroon">c<sub>2</sub></font>, <font color="Maroon">c<sub>3</sub></font>, <font color="Maroon">c<sub>4</sub></font> be  <a href="xreal_0.html#V1">real</a>  <a href="ordinal1.html#NM1" target="_self">number</a> ;<br/>







<a NAME="E1:84"/>
( <span class="p1"><a href="euclid.html#K23" target="_self">|[</a><span class="default"><font color="Maroon">c<sub>1</sub></font>,<font color="Maroon">c<sub>2</sub></font></span><a href="euclid.html#K23" target="_self">]|</a></span> <a href="euclid.html#K21" target="_self">`1</a>  <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>1</sub></font> &amp; <span class="p1"><a href="euclid.html#K23" target="_self">|[</a><span class="default"><font color="Maroon">c<sub>1</sub></font>,<font color="Maroon">c<sub>2</sub></font></span><a href="euclid.html#K23" target="_self">]|</a></span> <a href="euclid.html#K22" target="_self">`2</a>  <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>2</sub></font> &amp; <span class="p1"><a href="euclid.html#K23" target="_self">|[</a><span class="default"><font color="Maroon">c<sub>3</sub></font>,<font color="Maroon">c<sub>4</sub></font></span><a href="euclid.html#K23" target="_self">]|</a></span> <a href="euclid.html#K21" target="_self">`1</a>  <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>3</sub></font> &amp; <span class="p1"><a href="euclid.html#K23" target="_self">|[</a><span class="default"><font color="Maroon">c<sub>3</sub></font>,<font color="Maroon">c<sub>4</sub></font></span><a href="euclid.html#K23" target="_self">]|</a></span> <a href="euclid.html#K22" target="_self">`2</a>  <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>4</sub></font> )
 
<b>by </b><i><a class="ref" href="euclid.html#T56" target="_self">Th56</a></i>;<br/>
<b>hence </b><a NAME="E2:84"/>
<span class="p1"><a href="euclid.html#K23" target="_self">|[</a><span class="default"><font color="Maroon">c<sub>1</sub></font>,<font color="Maroon">c<sub>2</sub></font></span><a href="euclid.html#K23" target="_self">]|</a></span> <a href="euclid.html#K20" target="_self">-</a> <span class="p1"><a href="euclid.html#K23" target="_self">|[</a><span class="default"><font color="Maroon">c<sub>3</sub></font>,<font color="Maroon">c<sub>4</sub></font></span><a href="euclid.html#K23" target="_self">]|</a></span> <a href="hidden.html#R1">=</a> <span class="p1"><a href="euclid.html#K23" target="_self">|[</a><span class="default"><span class="p2">(<span class="default"><font color="Maroon">c<sub>1</sub></font> <a href="xcmplx_0.html#K6">-</a> <font color="Maroon">c<sub>3</sub></font></span>)</span>,<span class="p2">(<span class="default"><font color="Maroon">c<sub>2</sub></font> <a href="xcmplx_0.html#K6">-</a> <font color="Maroon">c<sub>4</sub></font></span>)</span></span><a href="euclid.html#K23" target="_self">]|</a></span>
 <b>by </b><i><a class="ref" href="euclid.html#T65" target="_self">Th65</a></i>;<br/>


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