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<b>let </b><font color="Maroon">c<sub>1</sub></font> be   <a href="relat_1.html#NM1">Relation</a>;<br/><b>let </b><font color="Maroon">c<sub>2</sub></font> be    <a href="hidden.html#M1">set</a> ;<br/>



<b>assume </b><a NAME="E1:178"/><i><font color="Green">E76</font></i>: 
<font color="Maroon">c<sub>2</sub></font> <a href="xboole_0.html#K3">/\</a> <span class="p1">(<span class="default"><a href="relat_1.html#K1" target="_self">dom</a> <font color="Maroon">c<sub>1</sub></font></span>)</span> <a href="hidden.html#R1">=</a>  <a href="xboole_0.html#K1">{}</a> 
 ; <i><font color="Red">:: according to </font></i><a class="ref" href="xboole_0.html#D7">XBOOLE_0:def 7</a><br/>

<b>thus </b><font color="Maroon">c<sub>1</sub></font> <a href="relat_1.html#K7" target="_self">|</a> <font color="Maroon">c<sub>2</sub></font> = 
<span class="p1">(<span class="default"><font color="Maroon">c<sub>1</sub></font> <a href="relat_1.html#K7" target="_self">|</a> <span class="p2">(<span class="default"><a href="relat_1.html#K1" target="_self">dom</a> <font color="Maroon">c<sub>1</sub></font></span>)</span></span>)</span> <a href="relat_1.html#K7" target="_self">|</a> <font color="Maroon">c<sub>2</sub></font>
<b>by </b><i><a class="ref" href="relat_1.html#T97" target="_self">Th97</a></i>
<br/>.= 
<font color="Maroon">c<sub>1</sub></font> <a href="relat_1.html#K7" target="_self">|</a> <a href="xboole_0.html#K1">{}</a> 
<b>by </b><i><a class="txt" href="relat_1.html#E1:178"><i><font color="Green">E76</font></i></a>, <a class="ref" href="relat_1.html#T100" target="_self">Th100</a></i>
<br/>.= 
 <a href="xboole_0.html#K1">{}</a> 
<b>by </b><i><a class="ref" href="relat_1.html#T110" target="_self">Th110</a></i>
;<br/>


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