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

<b>let </b><font color="Maroon">A</font> be   <a href="roughs_1.html#NM2">Tolerance_Space</a>;<br/><b>let </b><font color="Maroon">X</font> be   <a href="struct_0.html#NM2">Subset</a> of <font color="Maroon">A</font>;<br/>



<a NAME="E1:40"/>
( <font color="Maroon">X</font> <a href="hidden.html#R1">=</a>  <a href="roughs_1.html#K3" target="_self">LAp</a> <font color="Maroon">X</font> iff not <font color="Maroon">X</font> is <a href="roughs_1.html#V4" target="_self">rough</a> )
 
<b>by </b><i/>;<br/>
<b>hence </b><a NAME="E2:40"/>
( <font color="Maroon">X</font> <a href="hidden.html#R1">=</a>  <a href="roughs_1.html#K3" target="_self">LAp</a> <font color="Maroon">X</font> iff <font color="Maroon">X</font> <a href="hidden.html#R1">=</a>  <a href="roughs_1.html#K4" target="_self">UAp</a> <font color="Maroon">X</font> )
 <b>by </b><i/>;<br/>


</div>
