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<b>let </b><font color="Maroon">L</font> be   <a href="lattices.html#NM1">Lattice</a>;<br/>

<b>thus </b><a NAME="E1:61"/>
( <font color="Maroon">L</font> is <a href="lattices.html#V13">lower-bounded</a> implies <font color="Maroon">L</font> <a href="lattice2.html#K1" target="_self">.:</a>  is <a href="lattices.html#V14">upper-bounded</a> )
 <div><a class="txt" onclick="hs2(this)" href="javascript:()" title="61_1"><b>proof </b></a><div class="add">

<b>given </b><font color="Maroon">c</font> being   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">L</font><b> such that </b><a NAME="E1:61_1"/><i><font color="Green">E17</font></i>: 
for <font color="Olive">a</font> being  <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">L</font> holds <br/> ( <font color="Maroon">c</font> <a href="lattices.html#K4">"/\"</a> <font color="Olive">a</font> <a href="hidden.html#R1">=</a> <font color="Maroon">c</font> &amp; <font color="Olive">a</font> <a href="lattices.html#K4">"/\"</a> <font color="Maroon">c</font> <a href="hidden.html#R1">=</a> <font color="Maroon">c</font> )
 ; <i><font color="Red">:: according to </font></i><a class="ref" href="lattices.html#D13">LATTICES:def 13</a><br/>

<b>reconsider </b><font color="Maroon">c'</font> = <font color="Maroon">c</font> as   <a href="struct_0.html#NM1">Element</a> of <span class="p1">(<span class="default"><font color="Maroon">L</font> <a href="lattice2.html#K1" target="_self">.:</a> </span>)</span> ;<br/>
<b>take </b>
<font color="Maroon">c'</font>
; <i><font color="Red">:: according to </font></i><a class="ref" href="lattices.html#D14">LATTICES:def 14</a><br/>

<b>let </b><font color="Maroon">a'</font> be   <a href="struct_0.html#NM1">Element</a> of <span class="p1">(<span class="default"><font color="Maroon">L</font> <a href="lattice2.html#K1" target="_self">.:</a> </span>)</span>;<br/>

<b>reconsider </b><font color="Maroon">a</font> = <font color="Maroon">a'</font> as   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">L</font> ;<br/>
<b>thus </b><font color="Maroon">c'</font> <a href="lattices.html#K3">"\/"</a> <font color="Maroon">a'</font> = 
<font color="Maroon">c</font> <a href="lattices.html#K4">"/\"</a> <font color="Maroon">a</font>

<br/>.= 
<font color="Maroon">c'</font>
<b>by </b><i/>
;<br/>

<b>hence </b><a NAME="E5:61_1"/>
<font color="Maroon">a'</font> <a href="lattices.html#K3">"\/"</a> <font color="Maroon">c'</font> <a href="hidden.html#R1">=</a> <font color="Maroon">c'</font>
 ;<br/>


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

<b>given </b><font color="Maroon">c</font> being   <a href="struct_0.html#NM1">Element</a> of <span class="p1">(<span class="default"><font color="Maroon">L</font> <a href="lattice2.html#K1" target="_self">.:</a> </span>)</span><b> such that </b><a NAME="E2:61"/><i><font color="Green">E18</font></i>: 
for <font color="Olive">a</font> being  <a href="struct_0.html#NM1">Element</a> of <span class="p1">(<span class="default"><font color="Maroon">L</font> <a href="lattice2.html#K1" target="_self">.:</a> </span>)</span> holds <br/> ( <font color="Maroon">c</font> <a href="lattices.html#K3">"\/"</a> <font color="Olive">a</font> <a href="hidden.html#R1">=</a> <font color="Maroon">c</font> &amp; <font color="Olive">a</font> <a href="lattices.html#K3">"\/"</a> <font color="Maroon">c</font> <a href="hidden.html#R1">=</a> <font color="Maroon">c</font> )
 ; <i><font color="Red">:: according to </font></i><a class="ref" href="lattices.html#D14">LATTICES:def 14</a><br/>

<b>reconsider </b><font color="Maroon">c'</font> = <font color="Maroon">c</font> as   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">L</font> ;<br/>
<b>take </b>
<font color="Maroon">c'</font>
; <i><font color="Red">:: according to </font></i><a class="ref" href="lattices.html#D13">LATTICES:def 13</a><br/>

<b>let </b><font color="Maroon">a'</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">L</font>;<br/>

<b>reconsider </b><font color="Maroon">a</font> = <font color="Maroon">a'</font> as   <a href="struct_0.html#NM1">Element</a> of <span class="p1">(<span class="default"><font color="Maroon">L</font> <a href="lattice2.html#K1" target="_self">.:</a> </span>)</span> ;<br/>
<b>thus </b><font color="Maroon">c'</font> <a href="lattices.html#K4">"/\"</a> <font color="Maroon">a'</font> = 
<font color="Maroon">c</font> <a href="lattices.html#K3">"\/"</a> <font color="Maroon">a</font>

<br/>.= 
<font color="Maroon">c'</font>
<b>by </b><i/>
;<br/>

<b>hence </b><a NAME="E6:61"/>
<font color="Maroon">a'</font> <a href="lattices.html#K4">"/\"</a> <font color="Maroon">c'</font> <a href="hidden.html#R1">=</a> <font color="Maroon">c'</font>
 ;<br/>


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