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<b>let </b><font color="Maroon">p</font> be    <a href="subset_1.html#M1">Element</a> of  <a href="intpro_1.html#K1" target="_self">MC-wff</a> ;<br/><b>let </b><font color="Maroon">q</font> be    <a href="subset_1.html#M1">Element</a> of  <a href="intpro_1.html#K1" target="_self">MC-wff</a> ;<br/><b>let </b><font color="Maroon">s</font> be    <a href="subset_1.html#M1">Element</a> of  <a href="intpro_1.html#K1" target="_self">MC-wff</a> ;<br/>





<b>set </b><font color="Maroon">P</font> = <font color="Maroon">p</font> <a href="intpro_1.html#K4" target="_self">'&amp;'</a> <font color="Maroon">q</font>;<br/>
<a NAME="E1:81"/><i><font color="Green">E26</font></i>: 
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">p</font> <a href="intpro_1.html#K4" target="_self">'&amp;'</a> <font color="Maroon">q</font></span>)</span> <a href="intpro_1.html#K3" target="_self">=&gt;</a> <font color="Maroon">p</font></span>)</span> <a href="intpro_1.html#K3" target="_self">=&gt;</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><font color="Maroon">p</font> <a href="intpro_1.html#K4" target="_self">'&amp;'</a> <font color="Maroon">q</font></span>)</span> <a href="intpro_1.html#K4" target="_self">'&amp;'</a> <font color="Maroon">s</font></span>)</span> <a href="intpro_1.html#K3" target="_self">=&gt;</a> <span class="p2">(<span class="default"><font color="Maroon">p</font> <a href="intpro_1.html#K4" target="_self">'&amp;'</a> <font color="Maroon">s</font></span>)</span></span>)</span> <a href="hidden.html#R2">in</a>  <a href="intpro_1.html#K8" target="_self">IPC-Taut</a> 
 
<b>by </b><i/>;<br/>
<a NAME="E2:81"/>
<span class="p1">(<span class="default"><font color="Maroon">p</font> <a href="intpro_1.html#K4" target="_self">'&amp;'</a> <font color="Maroon">q</font></span>)</span> <a href="intpro_1.html#K3" target="_self">=&gt;</a> <font color="Maroon">p</font> <a href="hidden.html#R2">in</a>  <a href="intpro_1.html#K8" target="_self">IPC-Taut</a> 
 
<b>by </b><i/>;<br/>
<b>hence </b><a NAME="E3:81"/>
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">p</font> <a href="intpro_1.html#K4" target="_self">'&amp;'</a> <font color="Maroon">q</font></span>)</span> <a href="intpro_1.html#K4" target="_self">'&amp;'</a> <font color="Maroon">s</font></span>)</span> <a href="intpro_1.html#K3" target="_self">=&gt;</a> <span class="p1">(<span class="default"><font color="Maroon">p</font> <a href="intpro_1.html#K4" target="_self">'&amp;'</a> <font color="Maroon">s</font></span>)</span> <a href="hidden.html#R2">in</a>  <a href="intpro_1.html#K8" target="_self">IPC-Taut</a> 
 <b>by </b><i>, </i>;<br/>


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