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



<b>assume </b><a NAME="E1:92"/>
 <a href="relat_1.html#K1" target="_self">dom</a> <font color="Maroon">R</font> <a href="tarski.html#R1">c=</a> <font color="Maroon">X</font>
 ;<br/>

<a NAME="E2:92"/><b>then </b>
( <font color="Maroon">R</font> <a href="tarski.html#R1">c=</a> <span class="p1"><a href="zfmisc_1.html#K2">[:</a><span class="default"><span class="p2">(<span class="default"><a href="relat_1.html#K1" target="_self">dom</a> <font color="Maroon">R</font></span>)</span>,<span class="p2">(<span class="default"><a href="relat_1.html#K2" target="_self">rng</a> <font color="Maroon">R</font></span>)</span></span><a href="zfmisc_1.html#K2">:]</a></span> &amp; <span class="p1"><a href="zfmisc_1.html#K2">[:</a><span class="default"><span class="p2">(<span class="default"><a href="relat_1.html#K1" target="_self">dom</a> <font color="Maroon">R</font></span>)</span>,<span class="p2">(<span class="default"><a href="relat_1.html#K2" target="_self">rng</a> <font color="Maroon">R</font></span>)</span></span><a href="zfmisc_1.html#K2">:]</a></span> <a href="tarski.html#R1">c=</a> <span class="p1"><a href="zfmisc_1.html#K2">[:</a><span class="default"><font color="Maroon">X</font>,<span class="p2">(<span class="default"><a href="relat_1.html#K2" target="_self">rng</a> <font color="Maroon">R</font></span>)</span></span><a href="zfmisc_1.html#K2">:]</a></span> )
 
<b>by </b><i>, <a class="ref" href="zfmisc_1.html#T118">ZFMISC_1:118</a></i>;<br/>
<a NAME="E3:92"/><b>then </b>
( <font color="Maroon">R</font> <a href="tarski.html#R1">c=</a> <span class="p1"><a href="zfmisc_1.html#K2">[:</a><span class="default"><font color="Maroon">X</font>,<span class="p2">(<span class="default"><a href="relat_1.html#K2" target="_self">rng</a> <font color="Maroon">R</font></span>)</span></span><a href="zfmisc_1.html#K2">:]</a></span> &amp; <font color="Maroon">R</font> <a href="relat_1.html#K7" target="_self">|</a> <font color="Maroon">X</font> <a href="hidden.html#R1">=</a> <font color="Maroon">R</font> <a href="xboole_0.html#K3">/\</a> <span class="p1"><a href="zfmisc_1.html#K2">[:</a><span class="default"><font color="Maroon">X</font>,<span class="p2">(<span class="default"><a href="relat_1.html#K2" target="_self">rng</a> <font color="Maroon">R</font></span>)</span></span><a href="zfmisc_1.html#K2">:]</a></span> )
 
<b>by </b><i>, <a class="ref" href="xboole_1.html#T1">XBOOLE_1:1</a></i>;<br/>
<b>hence </b><a NAME="E4:92"/>
<font color="Maroon">R</font> <a href="relat_1.html#K7" target="_self">|</a> <font color="Maroon">X</font> <a href="hidden.html#R1">=</a> <font color="Maroon">R</font>
 <b>by </b><i><a class="ref" href="xboole_1.html#T28">XBOOLE_1:28</a></i>;<br/>


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