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<b>let </b><font color="Maroon" title="c1">Y</font> be  non <a href="struct_0.html#V2" title="STRUCT_0:attr.2">empty</a> <a href="tdlat_3.html#V4" title="TDLAT_3:attr.4">extremally_disconnected</a> <a href="pre_topc.html#NM1" title="PRE_TOPC:NM.1">TopSpace</a>; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> (  <a href="tdlat_1.html#NK3" title="TDLAT_1:NK.3">D-Union</a> <font color="Maroon" title="c1">Y</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="tdlat_1.html#NK15" title="TDLAT_1:NK.15">OPD-Union</a> <font color="Maroon" title="c1">Y</font> &amp;  <a href="tdlat_1.html#NK5" title="TDLAT_1:NK.5">D-Meet</a> <font color="Maroon" title="c1">Y</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="tdlat_1.html#NK17" title="TDLAT_1:NK.17">OPD-Meet</a> <font color="Maroon" title="c1">Y</font> )</span><br/>

<a NAME="E1:68"/><i><font color="Green" title="E36">A1</font></i>: 
 <a href="tdlat_1.html#K1" title="TDLAT_1:func.1">Domains_of</a> <font color="Maroon" title="c1">Y</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="tdlat_1.html#K9" title="TDLAT_1:func.9">Open_Domains_of</a> <font color="Maroon" title="c1">Y</font>
 
<b>by </b><i><a class="ref" href="tdlat_3.html#T44" target="_self" title="TDLAT_3:th.44">Th44</a></i>;<br/>
<b>hence </b> <a href="tdlat_1.html#NK3" title="TDLAT_1:NK.3">D-Union</a> <font color="Maroon" title="c1">Y</font> = 
<span class="p1">(<span class="default"><a href="tdlat_1.html#NK3" title="TDLAT_1:NK.3">D-Union</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="realset1.html#K1" title="REALSET1:func.1">||</a> <span class="p1">(<span class="default"><a href="tdlat_1.html#K9" title="TDLAT_1:func.9">Open_Domains_of</a> <font color="Maroon" title="c1">Y</font></span>)</span>
<b>by </b><i><a class="ref" href="funct_2.html#T40" title="FUNCT_2:th.40">FUNCT_2:40</a></i>
<br/>.= 
 <a href="tdlat_1.html#NK15" title="TDLAT_1:NK.15">OPD-Union</a> <font color="Maroon" title="c1">Y</font>
<b>by </b><i><a class="ref" href="tdlat_1.html#T42" title="TDLAT_1:th.42">TDLAT_1:42</a></i>
;<br/> <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide">  <a href="tdlat_1.html#NK5" title="TDLAT_1:NK.5">D-Meet</a> <font color="Maroon" title="c1">Y</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="tdlat_1.html#NK17" title="TDLAT_1:NK.17">OPD-Meet</a> <font color="Maroon" title="c1">Y</font></span><br/>

<b>thus </b> <a href="tdlat_1.html#NK5" title="TDLAT_1:NK.5">D-Meet</a> <font color="Maroon" title="c1">Y</font> = 
<span class="p1">(<span class="default"><a href="tdlat_1.html#NK5" title="TDLAT_1:NK.5">D-Meet</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="realset1.html#K1" title="REALSET1:func.1">||</a> <span class="p1">(<span class="default"><a href="tdlat_1.html#K9" title="TDLAT_1:func.9">Open_Domains_of</a> <font color="Maroon" title="c1">Y</font></span>)</span>
<b>by </b><i><a class="txt" href="tdlat_3.html#E1:68"><i><font color="Green" title="E36">A1</font></i></a>, <a class="ref" href="funct_2.html#T40" title="FUNCT_2:th.40">FUNCT_2:40</a></i>
<br/>.= 
 <a href="tdlat_1.html#NK17" title="TDLAT_1:NK.17">OPD-Meet</a> <font color="Maroon" title="c1">Y</font>
<b>by </b><i><a class="ref" href="tdlat_1.html#T43" title="TDLAT_1:th.43">TDLAT_1:43</a></i>
; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> verum</span><br/>


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