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<b>let </b><font color="Maroon" title="c1">A</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ;<br/>

<a NAME="E1:79"/>
 <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="normform.html#K8" title="NORMFORM:func.8">Normal_forms_on</a> <font color="Maroon" title="c1">A</font>
 
<b>by </b><i><a class="txt" href="normform.html#E62"><i><font color="Green" title="E21">Lm4</font></i></a></i>;<br/>
<b>then reconsider </b><font color="Maroon" title="c2">Z</font> =  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  as   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <span class="p1">(<span class="default"><a href="normform.html#K12" title="NORMFORM:func.12">NormForm</a> <font color="Maroon" title="c1">A</font></span>)</span> <b>by </b><i><a class="ref" href="normform.html#D14" target="_self" title="NORMFORM:def.14">Def14</a></i>;<br/>
<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="79_1"><b>now </b></a><div class="add"><b>let </b><font color="Maroon" title="c3">u</font> be   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <span class="p1">(<span class="default"><a href="normform.html#K12" title="NORMFORM:func.12">NormForm</a> <font color="Maroon" title="c1">A</font></span>)</span>;<br/><b>reconsider </b><font color="Maroon" title="c4">z</font> = <font color="Maroon" title="c2">Z</font>, <font color="Maroon" title="c5">u'</font> = <font color="Maroon" title="c3">u</font> as    <a href="subset_1.html#M2" title="SUBSET_1:mode.2">Element</a> of  <a href="normform.html#K8" title="NORMFORM:func.8">Normal_forms_on</a> <font color="Maroon" title="c1">A</font> <b>by </b><i><a class="ref" href="normform.html#D14" target="_self" title="NORMFORM:def.14">Def14</a></i>;<br/><b>thus </b><font color="Maroon" title="c2">Z</font> <a href="lattices.html#K3" title="LATTICES:func.3">"\/"</a> <font color="Maroon" title="c3">u</font> = 
 <a href="normform.html#K9" title="NORMFORM:func.9">mi</a> <span class="p1">(<span class="default"><font color="Maroon" title="c4">z</font> <a href="setwiseo.html#K5" title="SETWISEO:func.5">\/</a> <font color="Maroon" title="c5">u'</font></span>)</span>
<b>by </b><i><a class="ref" href="normform.html#D14" target="_self" title="NORMFORM:def.14">Def14</a></i>
<br/>.= 
<font color="Maroon" title="c3">u</font>
<b>by </b><i><a class="ref" href="normform.html#T66" target="_self" title="NORMFORM:th.66">Th66</a></i>
;<br/></div><b>end;</b></div>
<b>hence </b><a NAME="E4:79"/>
 <a href="lattices.html#K5" title="LATTICES:func.5">Bottom</a> <span class="p1">(<span class="default"><a href="normform.html#K12" title="NORMFORM:func.12">NormForm</a> <font color="Maroon" title="c1">A</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a> 
 <b>by </b><i><a class="ref" href="lattice2.html#T21" title="LATTICE2:th.21">LATTICE2:21</a></i>;<br/>


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