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<b>let </b><font color="Maroon">G1</font> be   <a href="graph_1.html#NM1">Graph</a>;<br/><b>let </b><font color="Maroon">G</font> be   <a href="graph_1.html#NM1">Graph</a>;<br/><b>let </b><font color="Maroon">G2</font> be   <a href="graph_1.html#NM1">Graph</a>;<br/>





<b>assume </b><a NAME="E1:70"/>
( <font color="Maroon">G1</font> <a href="hidden.html#R2">in</a>  <a href="graph_1.html#K7" target="_self">bool</a> <font color="Maroon">G</font> &amp; <font color="Maroon">G2</font> <a href="hidden.html#R2">in</a>  <a href="graph_1.html#K7" target="_self">bool</a> <font color="Maroon">G</font> )
 ;<br/>

<a NAME="E2:70"/><b>then </b>
( <font color="Maroon">G1</font> is    <a href="graph_1.html#M3" target="_self">Subgraph</a> of <font color="Maroon">G</font> &amp; <font color="Maroon">G2</font> is    <a href="graph_1.html#M3" target="_self">Subgraph</a> of <font color="Maroon">G</font> )
 
<b>by </b><i/>;<br/>
<a NAME="E3:70"/><b>then </b>
( <font color="Maroon">G1</font> <a href="graph_1.html#R4" target="_self">c=</a> <font color="Maroon">G</font> &amp; <font color="Maroon">G2</font> <a href="graph_1.html#R4" target="_self">c=</a> <font color="Maroon">G</font> )
 
<b>by </b><i/>;<br/>
<a NAME="E4:70"/><b>then </b>
<font color="Maroon">G1</font> <a href="graph_1.html#K1" target="_self">\/</a> <font color="Maroon">G2</font> <a href="graph_1.html#R4" target="_self">c=</a> <font color="Maroon">G</font>
 
<b>by </b><i/>;<br/>
<a NAME="E5:70"/><b>then </b>
<font color="Maroon">G1</font> <a href="graph_1.html#K1" target="_self">\/</a> <font color="Maroon">G2</font> is    <a href="graph_1.html#M3" target="_self">Subgraph</a> of <font color="Maroon">G</font>
 
<b>by </b><i/>;<br/>
<b>hence </b><a NAME="E6:70"/>
<font color="Maroon">G1</font> <a href="graph_1.html#K1" target="_self">\/</a> <font color="Maroon">G2</font> <a href="hidden.html#R2">in</a>  <a href="graph_1.html#K7" target="_self">bool</a> <font color="Maroon">G</font>
 <b>by </b><i/>;<br/>


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