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<b>let </b><font color="Maroon">c<sub>1</sub></font>, <font color="Maroon">c<sub>2</sub></font> be    <a href="subset_1.html#M1">Element</a> of  <a href="qc_lang1.html#K8">QC-WFF</a> ;<br/>



<b>thus </b> <a href="qc_lang2.html#K10" target="_self">the_left_disjunct_of</a> <span class="p1">(<span class="default"><font color="Maroon">c<sub>1</sub></font> <a href="qc_lang2.html#K3" target="_self">'or'</a> <font color="Maroon">c<sub>2</sub></font></span>)</span> = 
 <a href="qc_lang1.html#K17">the_argument_of</a> <span class="p1">(<span class="default"><a href="qc_lang1.html#K18">the_left_argument_of</a> <span class="p2">(<span class="default"><a href="qc_lang1.html#K17">the_argument_of</a> <span class="p3">(<span class="default"><a href="qc_lang1.html#K12">'not'</a> <span class="p4">(<span class="default"><span class="p5">(<span class="default"><a href="qc_lang1.html#K12">'not'</a> <font color="Maroon">c<sub>1</sub></font></span>)</span> <a href="qc_lang1.html#K13">'&amp;'</a> <span class="p5">(<span class="default"><a href="qc_lang1.html#K12">'not'</a> <font color="Maroon">c<sub>2</sub></font></span>)</span></span>)</span></span>)</span></span>)</span></span>)</span>

<br/>.= 
 <a href="qc_lang1.html#K17">the_argument_of</a> <span class="p1">(<span class="default"><a href="qc_lang1.html#K18">the_left_argument_of</a> <span class="p2">(<span class="default"><span class="p3">(<span class="default"><a href="qc_lang1.html#K12">'not'</a> <font color="Maroon">c<sub>1</sub></font></span>)</span> <a href="qc_lang1.html#K13">'&amp;'</a> <span class="p3">(<span class="default"><a href="qc_lang1.html#K12">'not'</a> <font color="Maroon">c<sub>2</sub></font></span>)</span></span>)</span></span>)</span>
<b>by </b><i><a class="ref" href="qc_lang2.html#T2" target="_self">Th2</a></i>
<br/>.= 
 <a href="qc_lang1.html#K17">the_argument_of</a> <span class="p1">(<span class="default"><a href="qc_lang1.html#K12">'not'</a> <font color="Maroon">c<sub>1</sub></font></span>)</span>
<b>by </b><i><a class="ref" href="qc_lang2.html#T5" target="_self">Th5</a></i>
<br/>.= 
<font color="Maroon">c<sub>1</sub></font>
<b>by </b><i><a class="ref" href="qc_lang2.html#T2" target="_self">Th2</a></i>
;<br/>

<b>thus </b> <a href="qc_lang2.html#K11" target="_self">the_right_disjunct_of</a> <span class="p1">(<span class="default"><font color="Maroon">c<sub>1</sub></font> <a href="qc_lang2.html#K3" target="_self">'or'</a> <font color="Maroon">c<sub>2</sub></font></span>)</span> = 
 <a href="qc_lang1.html#K17">the_argument_of</a> <span class="p1">(<span class="default"><a href="qc_lang1.html#K19">the_right_argument_of</a> <span class="p2">(<span class="default"><a href="qc_lang1.html#K17">the_argument_of</a> <span class="p3">(<span class="default"><a href="qc_lang1.html#K12">'not'</a> <span class="p4">(<span class="default"><span class="p5">(<span class="default"><a href="qc_lang1.html#K12">'not'</a> <font color="Maroon">c<sub>1</sub></font></span>)</span> <a href="qc_lang1.html#K13">'&amp;'</a> <span class="p5">(<span class="default"><a href="qc_lang1.html#K12">'not'</a> <font color="Maroon">c<sub>2</sub></font></span>)</span></span>)</span></span>)</span></span>)</span></span>)</span>

<br/>.= 
 <a href="qc_lang1.html#K17">the_argument_of</a> <span class="p1">(<span class="default"><a href="qc_lang1.html#K19">the_right_argument_of</a> <span class="p2">(<span class="default"><span class="p3">(<span class="default"><a href="qc_lang1.html#K12">'not'</a> <font color="Maroon">c<sub>1</sub></font></span>)</span> <a href="qc_lang1.html#K13">'&amp;'</a> <span class="p3">(<span class="default"><a href="qc_lang1.html#K12">'not'</a> <font color="Maroon">c<sub>2</sub></font></span>)</span></span>)</span></span>)</span>
<b>by </b><i><a class="ref" href="qc_lang2.html#T2" target="_self">Th2</a></i>
<br/>.= 
 <a href="qc_lang1.html#K17">the_argument_of</a> <span class="p1">(<span class="default"><a href="qc_lang1.html#K12">'not'</a> <font color="Maroon">c<sub>2</sub></font></span>)</span>
<b>by </b><i><a class="ref" href="qc_lang2.html#T5" target="_self">Th5</a></i>
<br/>.= 
<font color="Maroon">c<sub>2</sub></font>
<b>by </b><i><a class="ref" href="qc_lang2.html#T2" target="_self">Th2</a></i>
;<br/>

<b>thus </b><a NAME="E3:27"/>
 <a href="qc_lang1.html#K17">the_argument_of</a> <span class="p1">(<span class="default"><font color="Maroon">c<sub>1</sub></font> <a href="qc_lang2.html#K3" target="_self">'or'</a> <font color="Maroon">c<sub>2</sub></font></span>)</span> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><a href="qc_lang1.html#K12">'not'</a> <font color="Maroon">c<sub>1</sub></font></span>)</span> <a href="qc_lang1.html#K13">'&amp;'</a> <span class="p1">(<span class="default"><a href="qc_lang1.html#K12">'not'</a> <font color="Maroon">c<sub>2</sub></font></span>)</span>
 <b>by </b><i><a class="ref" href="qc_lang2.html#T2" target="_self">Th2</a></i>;<br/>


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