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

<b>let </b><font color="Maroon" title="c1">x</font>, <font color="Maroon" title="c2">y</font> be   <a href="supinf_1.html#NM3" title="SUPINF_1:NM.3">R_eal</a>;<br/><b>let </b><font color="Maroon" title="c3">a</font>, <font color="Maroon" title="c4">b</font> be   <a href="real_1.html#NM1" title="REAL_1:NM.1">Real</a>;<br/>



<b>assume </b><a NAME="E1:8"/><i><font color="Green" title="E10">A1</font></i>: 
<font color="Maroon" title="c1">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">a</font>
 ;<br/>

<b>assume </b><a NAME="E2:8"/>
<font color="Maroon" title="c2">y</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c4">b</font>
 ;<br/>

<a NAME="E3:8"/><b>then </b><i><font color="Green" title="E11">A2</font></i>: 
 <a href="supinf_2.html#K3" title="SUPINF_2:func.3">-</a> <font color="Maroon" title="c2">y</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="real_1.html#K1" title="REAL_1:func.1">-</a> <font color="Maroon" title="c4">b</font>
 
<b>by </b><i><a class="ref" href="supinf_2.html#T3" target="_self" title="SUPINF_2:th.3">Th3</a></i>;<br/>
<b>thus </b><a NAME="E4:8"/>
<font color="Maroon" title="c1">x</font> <a href="supinf_2.html#K4" title="SUPINF_2:func.4">-</a> <font color="Maroon" title="c2">y</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">a</font> <a href="real_1.html#K5" title="REAL_1:func.5">-</a> <font color="Maroon" title="c4">b</font>
 <b>by </b><i><a class="txt" href="supinf_2.html#E1:8"><i><font color="Green" title="E10">A1</font></i></a>, <a class="txt" href="supinf_2.html#E3:8"><i><font color="Green" title="E11">A2</font></i></a>, <a class="ref" href="supinf_2.html#T1" target="_self" title="SUPINF_2:th.1">Th1</a></i>;<br/>


</div>
