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

<b>let </b><font color="Maroon">X</font> be    <a href="hidden.html#M1">set</a> ;<br/><b>let </b><font color="Maroon">Y</font> be    <a href="hidden.html#M1">set</a> ;<br/><b>let </b><font color="Maroon">Z</font> be    <a href="hidden.html#M1">set</a> ;<br/>





<b>assume </b><a NAME="E1:8"/><i><font color="Green">E17</font></i>: 
( <font color="Maroon">X</font> <a href="hidden.html#R2">in</a> <font color="Maroon">Y</font> &amp; <font color="Maroon">X</font> <a href="xboole_0.html#R1">misses</a> <font color="Maroon">Z</font> )
 ;<br/>

<a NAME="E2:8"/><b>then </b>
 <a href="setfam_1.html#K1" target="_self">meet</a> <font color="Maroon">Y</font> <a href="tarski.html#R1">c=</a> <font color="Maroon">X</font>
 
<b>by </b><i/>;<br/>
<b>hence </b><a NAME="E3:8"/>
 <a href="setfam_1.html#K1" target="_self">meet</a> <font color="Maroon">Y</font> <a href="xboole_0.html#R1">misses</a> <font color="Maroon">Z</font>
 <b>by </b><i>, <a class="ref" href="xboole_1.html#T63">XBOOLE_1:63</a></i>;<br/>


</div>
