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<b>let </b><font color="Maroon">I</font> be    <a href="hidden.html#M1">set</a> ;<br/><b>let </b><font color="Maroon">X</font> be    <a href="pboole.html#M1" target="_self">ManySortedSet</a> of <font color="Maroon">I</font>;<br/><b>let </b><font color="Maroon">Y</font> be    <a href="pboole.html#M1" target="_self">ManySortedSet</a> of <font color="Maroon">I</font>;<br/>





<b>assume </b><a NAME="E1:32"/><i><font color="Green">E24</font></i>: 
<font color="Maroon">X</font> <a href="pboole.html#R2" target="_self">c=</a> <font color="Maroon">Y</font>
 ;<br/>

<b>hence </b><a NAME="E2:32"/>
<font color="Maroon">X</font> <a href="pboole.html#K2" target="_self">\/</a> <font color="Maroon">Y</font> <a href="pboole.html#R2" target="_self">c=</a> <font color="Maroon">Y</font>
 <b>by </b><i/>; <i><font color="Red">:: according to </font></i><a class="ref" href="pboole.html#D13" target="_self">PBOOLE:def 13</a><br/>

<b>thus </b><a NAME="E3:32"/>
<font color="Maroon">Y</font> <a href="pboole.html#R2" target="_self">c=</a> <font color="Maroon">X</font> <a href="pboole.html#K2" target="_self">\/</a> <font color="Maroon">Y</font>
 <b>by </b><i/>;<br/>

<b>thus </b><a NAME="E4:32"/>
<font color="Maroon">Y</font> <a href="pboole.html#K2" target="_self">\/</a> <font color="Maroon">X</font> <a href="pboole.html#R2" target="_self">c=</a> <font color="Maroon">Y</font>
 <b>by </b><i>, </i>; <i><font color="Red">:: according to </font></i><a class="ref" href="pboole.html#D13" target="_self">PBOOLE:def 13</a><br/>

<b>thus </b><a NAME="E5:32"/>
<font color="Maroon">Y</font> <a href="pboole.html#R2" target="_self">c=</a> <font color="Maroon">Y</font> <a href="pboole.html#K2" target="_self">\/</a> <font color="Maroon">X</font>
 <b>by </b><i/>;<br/>


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