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<b>let </b><font color="Maroon">a</font> be    <a href="hidden.html#M1">set</a> , <font color="Maroon">b</font> be    <a href="hidden.html#M1">set</a> ;<br/>

<div><b>hereby </b>
<div class="add"><b>assume </b><a NAME="E1:2_1"/>
<font color="Maroon">a</font> is   <a href="subset_1.html#NM2">Subset</a> of <font color="Maroon">b</font>
 ;<br/><a NAME="E2:2_1"/><b>then </b>
<font color="Maroon">a</font> <a href="hidden.html#R2">in</a>  <a href="zfmisc_1.html#K1">bool</a> <font color="Maroon">b</font>
 <b>by </b><i><a class="ref" href="subset_1.html#D2">SUBSET_1:def 2</a></i>;<br/><b>hence </b><a NAME="E3:2_1"/>
<font color="Maroon">a</font> <a href="tarski.html#R1">c=</a> <font color="Maroon">b</font>
 <b>by </b><i><a class="ref" href="zfmisc_1.html#D1">ZFMISC_1:def 1</a></i>;<br/></div>
<b>end;</b></div>

<b>assume </b><a NAME="E2:2"/>
<font color="Maroon">a</font> <a href="tarski.html#R1">c=</a> <font color="Maroon">b</font>
 ;<br/>

<a NAME="E3:2"/><b>then </b>
<font color="Maroon">a</font> <a href="hidden.html#R2">in</a>  <a href="zfmisc_1.html#K1">bool</a> <font color="Maroon">b</font>
 
<b>by </b><i><a class="ref" href="zfmisc_1.html#D1">ZFMISC_1:def 1</a></i>;<br/>
<b>hence </b><a NAME="E4:2"/>
<font color="Maroon">a</font> is   <a href="subset_1.html#NM2">Subset</a> of <font color="Maroon">b</font>
 <b>by </b><i><a class="ref" href="subset_1.html#D2">SUBSET_1:def 2</a></i>;<br/>


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