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<b>let </b><font color="Maroon">A</font> be    <a href="hidden.html#M1">set</a> ;<br/><b>let </b><font color="Maroon">K</font> be    <a href="subset_1.html#M2">Element</a> of  <a href="normform.html#K8" target="_self">Normal_forms_on</a> <font color="Maroon">A</font>;<br/><b>let </b><font color="Maroon">L</font> be    <a href="subset_1.html#M2">Element</a> of  <a href="normform.html#K8" target="_self">Normal_forms_on</a> <font color="Maroon">A</font>;<br/>





<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="63_1"><b>now </b></a><div class="add"><b>let </b><font color="Maroon">a</font> be    <a href="subset_1.html#M2">Element</a> of  <a href="normform.html#K7" target="_self">DISJOINT_PAIRS</a> <font color="Maroon">A</font>;<br/><b>assume </b><a NAME="E1:63_1"/><i><font color="Green">E29</font></i>: 
<font color="Maroon">a</font> <a href="hidden.html#R2">in</a>  <a href="normform.html#K9" target="_self">mi</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">K</font> <a href="normform.html#K10" target="_self">^</a> <font color="Maroon">L</font></span>)</span> <a href="setwiseo.html#K5">\/</a> <font color="Maroon">L</font></span>)</span>
 ;<br/><a NAME="E2:63_1"/><b>then </b>
<font color="Maroon">a</font> <a href="hidden.html#R2">in</a> <span class="p1">(<span class="default"><font color="Maroon">K</font> <a href="normform.html#K10" target="_self">^</a> <font color="Maroon">L</font></span>)</span> <a href="setwiseo.html#K5">\/</a> <font color="Maroon">L</font>
 <b>by </b><i><a class="txt" href="normform.html#E3:63_1"><i><font color="Green">E30</font></i></a></i>;<br/><a NAME="E3:63_1"/><b>then </b><i><font color="Green">E30</font></i>: 
( <font color="Maroon">a</font> <a href="hidden.html#R2">in</a> <font color="Maroon">K</font> <a href="normform.html#K10" target="_self">^</a> <font color="Maroon">L</font> or <font color="Maroon">a</font> <a href="hidden.html#R2">in</a> <font color="Maroon">L</font> )
 <b>by </b><i><a class="ref" href="xboole_0.html#D2">XBOOLE_0:def 2</a></i>;<br/><div><i><font color="Green">E44</font></i>: <a class="txt" onclick="hs2(this)" href="javascript:()" title="63_1_1"><b>now </b></a><div class="add"><b>assume </b><a NAME="E1:63_1_1"/>
<font color="Maroon">a</font> <a href="hidden.html#R2">in</a> <font color="Maroon">K</font> <a href="normform.html#K10" target="_self">^</a> <font color="Maroon">L</font>
 ;<br/><b>then consider </b><font color="Maroon">b</font> being    <a href="subset_1.html#M2">Element</a> of  <a href="normform.html#K7" target="_self">DISJOINT_PAIRS</a> <font color="Maroon">A</font><b> such that </b><br/><a NAME="E3:63_1_1"/><i><font color="Green">E45</font></i>: 
<font color="Maroon">b</font> <a href="hidden.html#R2">in</a> <font color="Maroon">L</font>
 <b>and </b><br/><a NAME="E4:63_1_1"/><i><font color="Green">E47</font></i>: 
<font color="Maroon">b</font> <a href="normform.html#R1" target="_self">c=</a> <font color="Maroon">a</font>
 <b>by </b><i><a class="txt" href="normform.html#E4:63_1_1"><i><font color="Green">E47</font></i></a></i>;<br/><a NAME="E5:63_1_1"/>
<font color="Maroon">b</font> <a href="hidden.html#R2">in</a> <span class="p1">(<span class="default"><font color="Maroon">K</font> <a href="normform.html#K10" target="_self">^</a> <font color="Maroon">L</font></span>)</span> <a href="setwiseo.html#K5">\/</a> <font color="Maroon">L</font>
 <b>by </b><i>, <a class="ref" href="xboole_0.html#D2">XBOOLE_0:def 2</a></i>;<br/><b>hence </b><a NAME="E6:63_1_1"/>
<font color="Maroon">a</font> <a href="hidden.html#R2">in</a> <font color="Maroon">L</font>
 <b>by </b><i>, , , <a class="txt" href="normform.html#E3:63_1"><i><font color="Green">E30</font></i></a></i>;<br/></div><b>end;</b></div><div><a class="txt" onclick="hs2(this)" href="javascript:()" title="63_1_2"><b>now </b></a><div class="add"><b>let </b><font color="Maroon">b</font> be    <a href="subset_1.html#M2">Element</a> of  <a href="normform.html#K7" target="_self">DISJOINT_PAIRS</a> <font color="Maroon">A</font>;<br/><b>assume </b><a NAME="E1:63_1_2"/>
<font color="Maroon">b</font> <a href="hidden.html#R2">in</a> <font color="Maroon">L</font>
 ;<br/><a NAME="E2:63_1_2"/><b>then </b>
<font color="Maroon">b</font> <a href="hidden.html#R2">in</a> <span class="p1">(<span class="default"><font color="Maroon">K</font> <a href="normform.html#K10" target="_self">^</a> <font color="Maroon">L</font></span>)</span> <a href="setwiseo.html#K5">\/</a> <font color="Maroon">L</font>
 <b>by </b><i><a class="ref" href="xboole_0.html#D2">XBOOLE_0:def 2</a></i>;<br/><b>hence </b><a NAME="E3:63_1_2"/>
( <font color="Maroon">b</font> <a href="normform.html#R1" target="_self">c=</a> <font color="Maroon">a</font> implies <font color="Maroon">b</font> <a href="hidden.html#R1">=</a> <font color="Maroon">a</font> )
 <b>by </b><i>, <a class="txt" href="normform.html#E3:63_1"><i><font color="Green">E30</font></i></a></i>;<br/></div><b>end;</b></div><b>hence </b><a NAME="E6:63_1"/>
<font color="Maroon">a</font> <a href="hidden.html#R2">in</a>  <a href="normform.html#K9" target="_self">mi</a> <font color="Maroon">L</font>
 <b>by </b><i>, , <a class="ref" href="normform.html#D6" target="_self">Def6</a></i>;<br/></div><b>end;</b></div>
<b>hence </b><a NAME="E2:63"/>
 <a href="normform.html#K9" target="_self">mi</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">K</font> <a href="normform.html#K10" target="_self">^</a> <font color="Maroon">L</font></span>)</span> <a href="setwiseo.html#K5">\/</a> <font color="Maroon">L</font></span>)</span> <a href="tarski.html#R1">c=</a>  <a href="normform.html#K9" target="_self">mi</a> <font color="Maroon">L</font>
 <b>by </b><i/>; <i><font color="Red">:: according to </font></i><a class="ref" href="xboole_0.html#D10">XBOOLE_0:def 10</a><br/>

<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="63_2"><b>now </b></a><div class="add"><b>let </b><font color="Maroon">a</font> be    <a href="subset_1.html#M2">Element</a> of  <a href="normform.html#K7" target="_self">DISJOINT_PAIRS</a> <font color="Maroon">A</font>;<br/><b>assume </b><a NAME="E1:63_2"/><i><font color="Green">E48</font></i>: 
<font color="Maroon">a</font> <a href="hidden.html#R2">in</a>  <a href="normform.html#K9" target="_self">mi</a> <font color="Maroon">L</font>
 ;<br/><a NAME="E2:63_2"/><b>then </b><i><font color="Green">E49</font></i>: 
<font color="Maroon">a</font> <a href="hidden.html#R2">in</a> <font color="Maroon">L</font>
 <b>by </b><i/>;<br/><a NAME="E3:63_2"/><b>then </b><i><font color="Green">E50</font></i>: 
<font color="Maroon">a</font> <a href="hidden.html#R2">in</a> <span class="p1">(<span class="default"><font color="Maroon">K</font> <a href="normform.html#K10" target="_self">^</a> <font color="Maroon">L</font></span>)</span> <a href="setwiseo.html#K5">\/</a> <font color="Maroon">L</font>
 <b>by </b><i><a class="ref" href="xboole_0.html#D2">XBOOLE_0:def 2</a></i>;<br/><div><a class="txt" onclick="hs2(this)" href="javascript:()" title="63_2_1"><b>now </b></a><div class="add"><b>let </b><font color="Maroon">b</font> be    <a href="subset_1.html#M2">Element</a> of  <a href="normform.html#K7" target="_self">DISJOINT_PAIRS</a> <font color="Maroon">A</font>;<br/><b>assume </b><a NAME="E1:63_2_1"/>
<font color="Maroon">b</font> <a href="hidden.html#R2">in</a> <span class="p1">(<span class="default"><font color="Maroon">K</font> <a href="normform.html#K10" target="_self">^</a> <font color="Maroon">L</font></span>)</span> <a href="setwiseo.html#K5">\/</a> <font color="Maroon">L</font>
 ;<br/><a NAME="E2:63_2_1"/><b>then </b><i><font color="Green">E82</font></i>: 
( <font color="Maroon">b</font> <a href="hidden.html#R2">in</a> <font color="Maroon">K</font> <a href="normform.html#K10" target="_self">^</a> <font color="Maroon">L</font> or <font color="Maroon">b</font> <a href="hidden.html#R2">in</a> <font color="Maroon">L</font> )
 <b>by </b><i><a class="ref" href="xboole_0.html#D2">XBOOLE_0:def 2</a></i>;<br/><b>assume </b><a NAME="E3:63_2_1"/><i><font color="Green">E83</font></i>: 
<font color="Maroon">b</font> <a href="normform.html#R1" target="_self">c=</a> <font color="Maroon">a</font>
 ;<br/><div><a class="txt" onclick="hs2(this)" href="javascript:()" title="63_2_1_1"><b>now </b></a><div class="add"><b>assume </b><a NAME="E1:63_2_1_1"/>
<font color="Maroon">b</font> <a href="hidden.html#R2">in</a> <font color="Maroon">K</font> <a href="normform.html#K10" target="_self">^</a> <font color="Maroon">L</font>
 ;<br/><b>then consider </b><font color="Maroon">c</font> being    <a href="subset_1.html#M2">Element</a> of  <a href="normform.html#K7" target="_self">DISJOINT_PAIRS</a> <font color="Maroon">A</font><b> such that </b><br/><a NAME="E3:63_2_1_1"/><i><font color="Green">E102</font></i>: 
<font color="Maroon">c</font> <a href="hidden.html#R2">in</a> <font color="Maroon">L</font>
 <b>and </b><br/><a NAME="E4:63_2_1_1"/><i><font color="Green">E103</font></i>: 
<font color="Maroon">c</font> <a href="normform.html#R1" target="_self">c=</a> <font color="Maroon">b</font>
 <b>by </b><i/>;<br/><a NAME="E5:63_2_1_1"/>
<font color="Maroon">c</font> <a href="normform.html#R1" target="_self">c=</a> <font color="Maroon">a</font>
 <b>by </b><i>, <a class="ref" href="normform.html#T45" target="_self">Th45</a>, </i>;<br/><a NAME="E6:63_2_1_1"/><b>then </b>
<font color="Maroon">c</font> <a href="hidden.html#R1">=</a> <font color="Maroon">a</font>
 <b>by </b><i><a class="txt" href="normform.html#E2:63_2"><i><font color="Green">E49</font></i></a>, <a class="ref" href="normform.html#T42" target="_self">Th42</a>, </i>;<br/><b>hence </b><a NAME="E7:63_2_1_1"/>
<font color="Maroon">b</font> <a href="hidden.html#R2">in</a> <font color="Maroon">L</font>
 <b>by </b><i><a class="txt" href="normform.html#E3:63_2"><i><font color="Green">E50</font></i></a>, , <a class="ref" href="normform.html#T45" target="_self">Th45</a>, </i>;<br/></div><b>end;</b></div><b>hence </b><a NAME="E5:63_2_1"/>
<font color="Maroon">b</font> <a href="hidden.html#R1">=</a> <font color="Maroon">a</font>
 <b>by </b><i><a class="txt" href="normform.html#E2:63_2"><i><font color="Green">E49</font></i></a>, , , </i>;<br/></div><b>end;</b></div><b>hence </b><a NAME="E5:63_2"/>
<font color="Maroon">a</font> <a href="hidden.html#R2">in</a>  <a href="normform.html#K9" target="_self">mi</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">K</font> <a href="normform.html#K10" target="_self">^</a> <font color="Maroon">L</font></span>)</span> <a href="setwiseo.html#K5">\/</a> <font color="Maroon">L</font></span>)</span>
 <b>by </b><i>, <a class="ref" href="normform.html#D6" target="_self">Def6</a></i>;<br/></div><b>end;</b></div>
<b>hence </b><a NAME="E4:63"/>
 <a href="normform.html#K9" target="_self">mi</a> <font color="Maroon">L</font> <a href="tarski.html#R1">c=</a>  <a href="normform.html#K9" target="_self">mi</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">K</font> <a href="normform.html#K10" target="_self">^</a> <font color="Maroon">L</font></span>)</span> <a href="setwiseo.html#K5">\/</a> <font color="Maroon">L</font></span>)</span>
 <b>by </b><i/>;<br/>


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