<?xml version="1.0"?>
<div class="add">

<b>reconsider </b><font color="Maroon">c<sub>3</sub></font> = <font color="Maroon">c<sub>1</sub></font> <a href="xboole_0.html#K3">/\</a> <font color="Maroon">c<sub>2</sub></font> as   <a href="subset_1.html#NM2">Subset</a> of <font color="Maroon">c<sub>1</sub></font> <b>by </b><i><a class="ref" href="xboole_1.html#T17">XBOOLE_1:17</a></i>;<br/>
<a NAME="E2:27_1_1"/>
<font color="Maroon">c<sub>3</sub></font> is <a href="setfam_1.html#V1">with_non-empty_elements</a>
 
;<br/>
<b>hence </b><a NAME="E3:27_1_1"/>
<font color="Maroon">c<sub>1</sub></font> <a href="xboole_0.html#K3">/\</a> <font color="Maroon">c<sub>2</sub></font> is <a href="setfam_1.html#V1">with_non-empty_elements</a>
 ;<br/>


</div>
