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<b>let </b><font color="Maroon">G1</font> be   <a href="glib_000.html#NM2">_Graph</a>;<br/><b>let </b><font color="Maroon">G2</font> be    <a href="glib_000.html#M2" target="_self">Subgraph</a> of <font color="Maroon">G1</font>;<br/><b>let </b><font color="Maroon">v1</font> be   <a href="glib_000.html#NM10">Vertex</a> of <font color="Maroon">G1</font>;<br/><b>let </b><font color="Maroon">v2</font> be   <a href="glib_000.html#NM10">Vertex</a> of <font color="Maroon">G2</font>;<br/>







<b>assume </b><a NAME="E1:176"/>
( <font color="Maroon">v1</font> <a href="hidden.html#R1">=</a> <font color="Maroon">v2</font> &amp; <font color="Maroon">v1</font> is <a href="glib_000.html#V10" target="_self">isolated</a> )
 ;<br/>

<a NAME="E2:176"/><b>then </b>
( <font color="Maroon">v1</font> <a href="glib_000.html#K29" target="_self">.edgesInOut()</a>  <a href="hidden.html#R1">=</a>  <a href="xboole_0.html#K1">{}</a>  &amp; <font color="Maroon">v2</font> <a href="glib_000.html#K29" target="_self">.edgesInOut()</a>  <a href="tarski.html#R1">c=</a> <font color="Maroon">v1</font> <a href="glib_000.html#K29" target="_self">.edgesInOut()</a>  )
 
<b>by </b><i>, </i>;<br/>
<a NAME="E3:176"/><b>then </b>
<font color="Maroon">v2</font> <a href="glib_000.html#K29" target="_self">.edgesInOut()</a>  <a href="hidden.html#R1">=</a>  <a href="xboole_0.html#K1">{}</a> 
 
<b>by </b><i><a class="ref" href="xboole_1.html#T3">XBOOLE_1:3</a></i>;<br/>
<b>hence </b><a NAME="E4:176"/>
<font color="Maroon">v2</font> is <a href="glib_000.html#V10" target="_self">isolated</a>
 <b>by </b><i/>;<br/>


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