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<b>let </b><font color="Maroon">c<sub>2</sub></font>, <font color="Maroon">c<sub>3</sub></font> be   <a href="card_1.html#NM1">Cardinal</a>;<br/>



<b>assume </b><a NAME="E1:73"/>
not <font color="Maroon">c<sub>2</sub></font> is <a href="finset_1.html#V1">finite</a>
 ;<br/>

<a NAME="E2:73"/><b>then </b><i><font color="Green">E52</font></i>: 
<font color="Maroon">c<sub>2</sub></font> <a href="card_2.html#K2">*`</a> <font color="Maroon">c<sub>2</sub></font> <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>2</sub></font>
 
<b>by </b><i><a class="ref" href="card_4.html#T77" target="_self">Th77</a></i>;<br/>
<b>assume </b><a NAME="E3:73"/><i><font color="Green">E53</font></i>: 
0 <a href="card_1.html#NR2" target="_self">&lt;`</a> <font color="Maroon">c<sub>3</sub></font>
 ;<br/>

<b>assume </b><a NAME="E4:73"/>
( <font color="Maroon">c<sub>3</sub></font> <a href="card_1.html#NR1" target="_self">&lt;=`</a> <font color="Maroon">c<sub>2</sub></font> or <font color="Maroon">c<sub>3</sub></font> <a href="card_1.html#NR2" target="_self">&lt;`</a> <font color="Maroon">c<sub>2</sub></font> )
 ;<br/>

<a NAME="E5:73"/><b>then </b>
( <font color="Maroon">c<sub>3</sub></font> <a href="card_1.html#NR1" target="_self">&lt;=`</a> <font color="Maroon">c<sub>2</sub></font> &amp; 1 <a href="card_1.html#NR1" target="_self">&lt;=`</a> <font color="Maroon">c<sub>3</sub></font> &amp; <font color="Maroon">c<sub>2</sub></font> <a href="card_1.html#NR1" target="_self">&lt;=`</a> <font color="Maroon">c<sub>2</sub></font> )
 
<b>by </b><i><a class="txt" href="card_4.html#E3:73"><i><font color="Green">E53</font></i></a>, <a class="ref" href="card_4.html#T24" target="_self">Th24</a>, <a class="ref" href="card_1.html#T13">CARD_1:13</a></i>;<br/>
<a NAME="E6:73"/><b>then </b>
( 1 <a href="card_2.html#K2">*`</a> <font color="Maroon">c<sub>2</sub></font> <a href="card_1.html#NR1" target="_self">&lt;=`</a> <font color="Maroon">c<sub>3</sub></font> <a href="card_2.html#K2">*`</a> <font color="Maroon">c<sub>2</sub></font> &amp; <font color="Maroon">c<sub>3</sub></font> <a href="card_2.html#K2">*`</a> <font color="Maroon">c<sub>2</sub></font> <a href="card_1.html#NR1" target="_self">&lt;=`</a> <font color="Maroon">c<sub>2</sub></font> <a href="card_2.html#K2">*`</a> <font color="Maroon">c<sub>2</sub></font> &amp; 1 <a href="card_2.html#K2">*`</a> <font color="Maroon">c<sub>2</sub></font> <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>2</sub></font> &amp; <font color="Maroon">c<sub>3</sub></font> <a href="card_2.html#K2">*`</a> <font color="Maroon">c<sub>2</sub></font> <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>2</sub></font> <a href="card_2.html#K2">*`</a> <font color="Maroon">c<sub>3</sub></font> )
 
<b>by </b><i><a class="ref" href="card_4.html#T68" target="_self">Th68</a>, <a class="ref" href="card_2.html#T33">CARD_2:33</a></i>;<br/>
<b>hence </b><a NAME="E7:73"/>
( <font color="Maroon">c<sub>2</sub></font> <a href="card_2.html#K2">*`</a> <font color="Maroon">c<sub>3</sub></font> <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>2</sub></font> &amp; <font color="Maroon">c<sub>3</sub></font> <a href="card_2.html#K2">*`</a> <font color="Maroon">c<sub>2</sub></font> <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>2</sub></font> )
 <b>by </b><i><a class="txt" href="card_4.html#E2:73"><i><font color="Green">E52</font></i></a>, <a class="ref" href="xboole_0.html#D10">XBOOLE_0:def 10</a></i>;<br/>


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