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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E204">Th81</font></span>: <a NAME="T280"><span class="comment"><font color="firebrick">:: GROUP_1A:280</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">G</font> being   <a href="group_1a.html#NM1" title="GROUP_1A:NM.1">addGroup</a><br/>  for <font color="Olive" title="b2">a</font>, <font color="Olive" title="b3">b</font> being   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Olive" title="b1">G</font> holds <br/> ( <font color="Olive" title="b2">a</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  <a href="group_1a.html#K30" title="GROUP_1A:func.30">con_class</a> <font color="Olive" title="b3">b</font> iff <font color="Olive" title="b2">a</font>,<font color="Olive" title="b3">b</font> <a href="group_1a.html#R3" title="GROUP_1A:pred.3">are_conjugated</a>  )</div></div>
