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<b>let </b><font color="Maroon">R</font> be  <a href="rewrite1.html#V4" target="_self">with_UN_property</a> <a href="relat_1.html#NM1">Relation</a>;<br/><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> , <font color="Maroon">c</font> be    <a href="hidden.html#M1">set</a> ;<br/>



<b>assume </b><b>that </b><br/><a NAME="E1:79"/><i><font color="Green">E21</font></i>: 
( <font color="Maroon">b</font> <a href="rewrite1.html#R3" target="_self">is_a_normal_form_wrt</a> <font color="Maroon">R</font> &amp; <font color="Maroon">R</font> <a href="rewrite1.html#R1" target="_self">reduces</a> <font color="Maroon">a</font>,<font color="Maroon">b</font> )
 <b>and </b><br/><a NAME="E2:79"/><i><font color="Green">E29</font></i>: 
( <font color="Maroon">c</font> <a href="rewrite1.html#R3" target="_self">is_a_normal_form_wrt</a> <font color="Maroon">R</font> &amp; <font color="Maroon">R</font> <a href="rewrite1.html#R1" target="_self">reduces</a> <font color="Maroon">a</font>,<font color="Maroon">c</font> )
 ; <i><font color="Red">:: according to </font></i><a class="ref" href="rewrite1.html#D6" target="_self">REWRITE1:def 6</a><br/>

<a NAME="E3:79"/>
<font color="Maroon">b</font>,<font color="Maroon">c</font> <a href="rewrite1.html#R6" target="_self">are_divergent_wrt</a> <font color="Maroon">R</font>
 
<b>by </b><i><a class="ref" href="rewrite1.html#D4" target="_self">Def4</a>, <a class="ref" href="rewrite1.html#T12" target="_self">Th12</a>, </i>;<br/>
<a NAME="E4:79"/><b>then </b>
<font color="Maroon">b</font>,<font color="Maroon">c</font> <a href="rewrite1.html#R2" target="_self">are_convertible_wrt</a> <font color="Maroon">R</font>
 
<b>by </b><i/>;<br/>
<b>hence </b><a NAME="E5:79"/>
<font color="Maroon">b</font> <a href="hidden.html#R1">=</a> <font color="Maroon">c</font>
 <b>by </b><i><a class="ref" href="rewrite1.html#D4" target="_self">Def4</a>, <a class="ref" href="rewrite1.html#T12" target="_self">Th12</a>, <a class="ref" href="rewrite1.html#T8" target="_self">Th8</a></i>;<br/>


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