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

<b>let </b><font color="Maroon">x</font> be   <a href="supinf_1.html#NM3">R_eal</a>, <font color="Maroon">y</font> be   <a href="supinf_1.html#NM3">R_eal</a>;<br/>

<b>thus </b><a NAME="E1:21"/>
( <font color="Maroon">x</font> <a href="xxreal_0.html#R1">&lt;=</a> <font color="Maroon">y</font> implies  <a href="supinf_2.html#K3" target="_self">-</a> <font color="Maroon">y</font> <a href="xxreal_0.html#R1">&lt;=</a>  <a href="supinf_2.html#K3" target="_self">-</a> <font color="Maroon">x</font> )
 <b>by </b><i><a class="ref" href="supinf_2.html#D2" target="_self">Def2</a></i>;<br/>

<a NAME="E2:21"/>
(  <a href="supinf_2.html#K3" target="_self">-</a> <font color="Maroon">y</font> <a href="xxreal_0.html#R1">&lt;=</a>  <a href="supinf_2.html#K3" target="_self">-</a> <font color="Maroon">x</font> implies  <a href="supinf_2.html#K3" target="_self">-</a> <span class="p1">(<span class="default"><a href="supinf_2.html#K3" target="_self">-</a> <font color="Maroon">x</font></span>)</span> <a href="xxreal_0.html#R1">&lt;=</a>  <a href="supinf_2.html#K3" target="_self">-</a> <span class="p1">(<span class="default"><a href="supinf_2.html#K3" target="_self">-</a> <font color="Maroon">y</font></span>)</span> )
 
<b>by </b><i><a class="ref" href="supinf_2.html#D2" target="_self">Def2</a></i>;<br/>
<b>hence </b><a NAME="E3:21"/>
(  <a href="supinf_2.html#K3" target="_self">-</a> <font color="Maroon">y</font> <a href="xxreal_0.html#R1">&lt;=</a>  <a href="supinf_2.html#K3" target="_self">-</a> <font color="Maroon">x</font> implies <font color="Maroon">x</font> <a href="xxreal_0.html#R1">&lt;=</a> <font color="Maroon">y</font> )
 ;<br/>


</div>
