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<b>let </b><font color="Maroon">G</font> be   <a href="glib_000.html#NM2">_Graph</a>;<br/>

<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="109_1"><b>now </b></a><div class="add"><b>let </b><font color="Maroon">x</font> be    <a href="hidden.html#M1">set</a> ;<br/><b>assume </b><a NAME="E1:109_1"/>
<font color="Maroon">x</font> <a href="hidden.html#R2">in</a>  <a href="glib_000.html#K5" target="_self">_GraphSelectors</a> 
 ;<br/><a NAME="E2:109_1"/><b>then </b>
( <font color="Maroon">x</font> <a href="hidden.html#R1">=</a>  <a href="glib_000.html#K1" target="_self">VertexSelector</a>  or <font color="Maroon">x</font> <a href="hidden.html#R1">=</a>  <a href="glib_000.html#K2" target="_self">EdgeSelector</a>  or <font color="Maroon">x</font> <a href="hidden.html#R1">=</a>  <a href="glib_000.html#K3" target="_self">SourceSelector</a>  or <font color="Maroon">x</font> <a href="hidden.html#R1">=</a>  <a href="glib_000.html#K4" target="_self">TargetSelector</a>  )
 <b>by </b><i><a class="ref" href="enumset1.html#D2">ENUMSET1:def 2</a></i>;<br/><b>hence </b><a NAME="E3:109_1"/>
<font color="Maroon">x</font> <a href="hidden.html#R2">in</a>  <a href="relat_1.html#K1">dom</a> <font color="Maroon">G</font>
 <b>by </b><i/>;<br/></div><b>end;</b></div>
<b>hence </b><a NAME="E2:109"/>
 <a href="glib_000.html#K5" target="_self">_GraphSelectors</a>  <a href="tarski.html#R1">c=</a>  <a href="relat_1.html#K1">dom</a> <font color="Maroon">G</font>
 <b>by </b><i><a class="ref" href="tarski.html#D3">TARSKI:def 3</a></i>;<br/>


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