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

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

<a NAME="E1:17"/>
(  <a href="seq_4.html#K5" target="_self">lower_bound</a> <span class="p1"><a href="seq_4.html#K1" target="_self">{</a><span class="default"><font color="Maroon">c<sub>1</sub></font></span><a href="seq_4.html#K1" target="_self">}</a></span> <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>1</sub></font> &amp;  <a href="seq_4.html#K4" target="_self">upper_bound</a> <span class="p1"><a href="seq_4.html#K1" target="_self">{</a><span class="default"><font color="Maroon">c<sub>1</sub></font></span><a href="seq_4.html#K1" target="_self">}</a></span> <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>1</sub></font> )
 
<b>by </b><i><a class="ref" href="seq_4.html#T22" target="_self">Th22</a></i>;<br/>
<b>hence </b><a NAME="E2:17"/>
 <a href="seq_4.html#K5" target="_self">lower_bound</a> <span class="p1"><a href="seq_4.html#K1" target="_self">{</a><span class="default"><font color="Maroon">c<sub>1</sub></font></span><a href="seq_4.html#K1" target="_self">}</a></span> <a href="hidden.html#R1">=</a>  <a href="seq_4.html#K4" target="_self">upper_bound</a> <span class="p1"><a href="seq_4.html#K1" target="_self">{</a><span class="default"><font color="Maroon">c<sub>1</sub></font></span><a href="seq_4.html#K1" target="_self">}</a></span>
 ;<br/>


</div>
