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<b>let </b><font color="Maroon" title="c1">G</font> be   <a href="group_1.html#NM1" title="GROUP_1:NM.1">Group</a>;<br/><b>let </b><font color="Maroon" title="c2">a</font>, <font color="Maroon" title="c3">b</font> be   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">G</font>;<br/>





<b>thus </b><a NAME="E1:86"/>
(  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c2">a</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c3">b</font> implies  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c2">a</font> <a href="xboole_0.html#NR5" title="XBOOLE_0:NR.5">meets</a>  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c3">b</font> )
 <div><a class="txt" onclick="hs2(this)" href="javascript:()" title="86_1"><b>proof </b></a><div class="add">

<b>assume </b><a NAME="E1:86_1"/>
 <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c2">a</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c3">b</font>
 ;<br/>

<a NAME="E2:86_1"/><b>then </b>
( <font color="Maroon" title="c2">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c3">b</font> &amp; <font color="Maroon" title="c2">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c2">a</font> )
 
<b>by </b><i><a class="ref" href="group_3.html#T96" target="_self" title="GROUP_3:th.96">Th96</a></i>;<br/>
<b>hence </b><a NAME="E3:86_1"/>
 <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c2">a</font> <a href="xboole_0.html#NR5" title="XBOOLE_0:NR.5">meets</a>  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c3">b</font>
 <b>by </b><i><a class="ref" href="xboole_0.html#T3" title="XBOOLE_0:th.3">XBOOLE_0:3</a></i>;<br/>


</div><b>end;</b></div>

<b>assume </b><a NAME="E2:86"/>
 <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c2">a</font> <a href="xboole_0.html#NR5" title="XBOOLE_0:NR.5">meets</a>  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c3">b</font>
 ;<br/>

<b>then consider </b><font color="Maroon" title="c4">x</font> being    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> <b> such that </b><br/><a NAME="E4:86"/><i><font color="Green" title="E65">A1</font></i>: 
( <font color="Maroon" title="c4">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c2">a</font> &amp; <font color="Maroon" title="c4">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c3">b</font> )
 <b>by </b><i><a class="ref" href="xboole_0.html#T3" title="XBOOLE_0:th.3">XBOOLE_0:3</a></i>;<br/>
<b>reconsider </b><font color="Maroon" title="c5">x</font> = <font color="Maroon" title="c4">x</font> as   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">G</font> <b>by </b><i><a class="txt" href="group_3.html#E4:86"><i><font color="Green" title="E65">A1</font></i></a></i>;<br/>
<b>thus </b><a NAME="E6:86"/>
 <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c2">a</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a>  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c3">b</font>
  <i><font color="Red">:: according to </font></i><a class="ref" href="xboole_0.html#D10" title="XBOOLE_0:def.10">XBOOLE_0:def 10</a><div><a class="txt" onclick="hs2(this)" href="javascript:()" title="86_2"><b>proof </b></a><div class="add">

<b>let </b><font color="Maroon" title="c6">y</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ; <i><font color="Red">:: according to </font></i><a class="ref" href="tarski.html#D3" title="TARSKI:def.3">TARSKI:def 3</a><br/>

<b>assume </b><a NAME="E1:86_2"/>
<font color="Maroon" title="c6">y</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c2">a</font>
 ;<br/>

<b>then consider </b><font color="Maroon" title="c7">g</font> being   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">G</font><b> such that </b><br/><a NAME="E3:86_2"/><i><font color="Green" title="E66">A2</font></i>: 
( <font color="Maroon" title="c7">g</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c6">y</font> &amp; <font color="Maroon" title="c2">a</font>,<font color="Maroon" title="c7">g</font> <a href="group_3.html#R2" title="GROUP_3:pred.2">are_conjugated</a>  )
 <b>by </b><i><a class="ref" href="group_3.html#T95" target="_self" title="GROUP_3:th.95">Th95</a></i>;<br/>
<a NAME="E4:86_2"/>
( <font color="Maroon" title="c5">x</font>,<font color="Maroon" title="c2">a</font> <a href="group_3.html#R2" title="GROUP_3:pred.2">are_conjugated</a>  &amp; <font color="Maroon" title="c5">x</font>,<font color="Maroon" title="c3">b</font> <a href="group_3.html#R2" title="GROUP_3:pred.2">are_conjugated</a>  )
 
<b>by </b><i><a class="txt" href="group_3.html#E4:86"><i><font color="Green" title="E65">A1</font></i></a>, <a class="ref" href="group_3.html#T96" target="_self" title="GROUP_3:th.96">Th96</a></i>;<br/>
<a NAME="E5:86_2"/><b>then </b>
( <font color="Maroon" title="c5">x</font>,<font color="Maroon" title="c7">g</font> <a href="group_3.html#R2" title="GROUP_3:pred.2">are_conjugated</a>  &amp; <font color="Maroon" title="c3">b</font>,<font color="Maroon" title="c5">x</font> <a href="group_3.html#R2" title="GROUP_3:pred.2">are_conjugated</a>  )
 
<b>by </b><i><a class="txt" href="group_3.html#E3:86_2"><i><font color="Green" title="E66">A2</font></i></a>, <a class="ref" href="group_3.html#T91" target="_self" title="GROUP_3:th.91">Th91</a></i>;<br/>
<a NAME="E6:86_2"/><b>then </b>
<font color="Maroon" title="c3">b</font>,<font color="Maroon" title="c7">g</font> <a href="group_3.html#R2" title="GROUP_3:pred.2">are_conjugated</a> 
 
<b>by </b><i><a class="ref" href="group_3.html#T91" target="_self" title="GROUP_3:th.91">Th91</a></i>;<br/>
<b>hence </b><a NAME="E7:86_2"/>
<font color="Maroon" title="c6">y</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c3">b</font>
 <b>by </b><i><a class="txt" href="group_3.html#E3:86_2"><i><font color="Green" title="E66">A2</font></i></a>, <a class="ref" href="group_3.html#T95" target="_self" title="GROUP_3:th.95">Th95</a></i>;<br/>


</div><b>end;</b></div>

<b>let </b><font color="Maroon" title="c6">y</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ; <i><font color="Red">:: according to </font></i><a class="ref" href="tarski.html#D3" title="TARSKI:def.3">TARSKI:def 3</a><br/>

<b>assume </b><a NAME="E7:86"/>
<font color="Maroon" title="c6">y</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c3">b</font>
 ;<br/>

<b>then consider </b><font color="Maroon" title="c7">g</font> being   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">G</font><b> such that </b><br/><a NAME="E9:86"/><i><font color="Green" title="E66">A3</font></i>: 
( <font color="Maroon" title="c7">g</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c6">y</font> &amp; <font color="Maroon" title="c3">b</font>,<font color="Maroon" title="c7">g</font> <a href="group_3.html#R2" title="GROUP_3:pred.2">are_conjugated</a>  )
 <b>by </b><i><a class="ref" href="group_3.html#T95" target="_self" title="GROUP_3:th.95">Th95</a></i>;<br/>
<a NAME="E10:86"/>
( <font color="Maroon" title="c5">x</font>,<font color="Maroon" title="c3">b</font> <a href="group_3.html#R2" title="GROUP_3:pred.2">are_conjugated</a>  &amp; <font color="Maroon" title="c5">x</font>,<font color="Maroon" title="c2">a</font> <a href="group_3.html#R2" title="GROUP_3:pred.2">are_conjugated</a>  )
 
<b>by </b><i><a class="txt" href="group_3.html#E4:86"><i><font color="Green" title="E65">A1</font></i></a>, <a class="ref" href="group_3.html#T96" target="_self" title="GROUP_3:th.96">Th96</a></i>;<br/>
<a NAME="E11:86"/><b>then </b>
( <font color="Maroon" title="c2">a</font>,<font color="Maroon" title="c5">x</font> <a href="group_3.html#R2" title="GROUP_3:pred.2">are_conjugated</a>  &amp; <font color="Maroon" title="c5">x</font>,<font color="Maroon" title="c7">g</font> <a href="group_3.html#R2" title="GROUP_3:pred.2">are_conjugated</a>  )
 
<b>by </b><i><a class="txt" href="group_3.html#E9:86"><i><font color="Green" title="E66">A3</font></i></a>, <a class="ref" href="group_3.html#T91" target="_self" title="GROUP_3:th.91">Th91</a></i>;<br/>
<a NAME="E12:86"/><b>then </b>
<font color="Maroon" title="c2">a</font>,<font color="Maroon" title="c7">g</font> <a href="group_3.html#R2" title="GROUP_3:pred.2">are_conjugated</a> 
 
<b>by </b><i><a class="ref" href="group_3.html#T91" target="_self" title="GROUP_3:th.91">Th91</a></i>;<br/>
<b>hence </b><a NAME="E13:86"/>
<font color="Maroon" title="c6">y</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="group_3.html#K7" title="GROUP_3:func.7">con_class</a> <font color="Maroon" title="c2">a</font>
 <b>by </b><i><a class="txt" href="group_3.html#E9:86"><i><font color="Green" title="E66">A3</font></i></a>, <a class="ref" href="group_3.html#T95" target="_self" title="GROUP_3:th.95">Th95</a></i>;<br/>


</div>
