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<b>let </b><font color="Maroon">L</font> be   <a href="lattices.html#NM8">B_Lattice</a>;<br/><b>let </b><font color="Maroon">X</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">L</font>;<br/><b>let </b><font color="Maroon">Y</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">L</font>;<br/>





<b>thus </b><font color="Maroon">X</font> <a href="boolealg.html#K3" target="_self">\+\</a> <font color="Maroon">Y</font> = 
<span class="p1">(<span class="default"><font color="Maroon">X</font> <a href="boolealg.html#K1" target="_self">\</a> <span class="p2">(<span class="default"><font color="Maroon">X</font> <a href="lattices.html#K4">"/\"</a> <font color="Maroon">Y</font></span>)</span></span>)</span> <a href="lattices.html#K3">"\/"</a> <span class="p1">(<span class="default"><font color="Maroon">Y</font> <a href="boolealg.html#K1" target="_self">\</a> <font color="Maroon">X</font></span>)</span>
<b>by </b><i/>
<br/>.= 
<span class="p1">(<span class="default"><font color="Maroon">X</font> <a href="boolealg.html#K1" target="_self">\</a> <span class="p2">(<span class="default"><font color="Maroon">X</font> <a href="lattices.html#K4">"/\"</a> <font color="Maroon">Y</font></span>)</span></span>)</span> <a href="lattices.html#K3">"\/"</a> <span class="p1">(<span class="default"><font color="Maroon">Y</font> <a href="boolealg.html#K1" target="_self">\</a> <span class="p2">(<span class="default"><font color="Maroon">X</font> <a href="lattices.html#K4">"/\"</a> <font color="Maroon">Y</font></span>)</span></span>)</span>
<b>by </b><i/>
<br/>.= 
<span class="p1">(<span class="default"><font color="Maroon">X</font> <a href="lattices.html#K3">"\/"</a> <font color="Maroon">Y</font></span>)</span> <a href="boolealg.html#K1" target="_self">\</a> <span class="p1">(<span class="default"><font color="Maroon">X</font> <a href="lattices.html#K4">"/\"</a> <font color="Maroon">Y</font></span>)</span>
<b>by </b><i><a class="ref" href="lattices.html#D11">LATTICES:def 11</a></i>
;<br/>


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