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<a NAME="E1:49_1_1"/>
for <font color="Olive">b<sub>1</sub></font> being   <a href="hidden.html#M1">set</a>  holds <br/>( <font color="Olive">b<sub>1</sub></font> <a href="hidden.html#R2">in</a>  <a href="prob_4.html#K4" target="_self">COM</a> <font color="Maroon">c<sub>2</sub></font>,<font color="Maroon">c<sub>3</sub></font> iff ex <font color="Olive">b<sub>2</sub></font> being   <a href="hidden.html#M1">set</a>  st <br/>( <font color="Olive">b<sub>2</sub></font> <a href="hidden.html#R2">in</a> <font color="Maroon">c<sub>2</sub></font> &amp; ex <font color="Olive">b<sub>3</sub></font> being   <a href="prob_4.html#M1" target="_self">thin</a> of <font color="Maroon">c<sub>3</sub></font> st <font color="Olive">b<sub>1</sub></font> <a href="hidden.html#R1">=</a> <font color="Olive">b<sub>2</sub></font> <a href="xboole_0.html#K2">\/</a> <font color="Olive">b<sub>3</sub></font> ) )
 
<b>by </b><i><a class="ref" href="prob_4.html#D5" target="_self">Def5</a></i>;<br/>
<b>hence </b><a NAME="E2:49_1_1"/>
 <a href="prob_4.html#K4" target="_self">COM</a> <font color="Maroon">c<sub>2</sub></font>,<font color="Maroon">c<sub>3</sub></font> is   <a href="prob_1.html#NM3">SigmaField</a> of <font color="Maroon">c<sub>1</sub></font>
 <b>by </b><i><a class="ref" href="prob_4.html#T35" target="_self">Th35</a></i>;<br/>


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