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<font color="Maroon" title="c1">S</font> <a href="xboole_0.html#K2" title="XBOOLE_0:func.2">\/</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">S</font> <a href="relat_1.html#K4" title="RELAT_1:func.4">~</a> </span>)</span> = 
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><font color="Maroon" title="c1">S</font> <a href="relat_1.html#K4" title="RELAT_1:func.4">~</a> </span>)</span> <a href="relat_1.html#K4" title="RELAT_1:func.4">~</a> </span>)</span> <a href="xboole_0.html#K2" title="XBOOLE_0:func.2">\/</a> <span class="p2">(<span class="default"><font color="Maroon" title="c1">S</font> <a href="relat_1.html#K4" title="RELAT_1:func.4">~</a> </span>)</span></span>)</span> <a href="relat_1.html#K4" title="RELAT_1:func.4">~</a> 
<b>by </b><i><a class="ref" href="relat_1.html#T40" title="RELAT_1:th.40">RELAT_1:40</a></i>
<br/>.= 
<span class="p1">(<span class="default"><font color="Maroon" title="c1">S</font> <a href="xboole_0.html#K2" title="XBOOLE_0:func.2">\/</a> <span class="p2">(<span class="default"><font color="Maroon" title="c1">S</font> <a href="relat_1.html#K4" title="RELAT_1:func.4">~</a> </span>)</span></span>)</span> <a href="relat_1.html#K4" title="RELAT_1:func.4">~</a> 

;<br/>
<b>hence </b><a NAME="E2:23_1_1"/>
<font color="Maroon" title="c1">S</font> <a href="xboole_0.html#K2" title="XBOOLE_0:func.2">\/</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">S</font> <a href="relat_1.html#K4" title="RELAT_1:func.4">~</a> </span>)</span> is <a href="relat_2.html#V3" title="RELAT_2:attr.3">symmetric</a>
 <b>by </b><i><a class="ref" href="relat_2.html#T30" title="RELAT_2:th.30">RELAT_2:30</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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