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<b>let </b><font color="Maroon">D</font> be  non <a href="xboole_0.html#V1">empty</a>  <a href="hidden.html#M1">set</a> ;<br/><b>let </b><font color="Maroon">F</font> be  non <a href="struct_0.html#V3">empty</a>  <a href="monoid_0.html#M2" target="_self">SubStr</a> of <font color="Maroon">D</font> <a href="monoid_0.html#K10" target="_self">*+^</a> ;<br/><b>let </b><font color="Maroon">p</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">F</font>, <font color="Maroon">q</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">F</font>;<br/>





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<font color="Maroon">H<sub>1</sub></font>(<font color="Maroon">F</font>) <a href="tarski.html#R1">c=</a> <font color="Maroon">H<sub>1</sub></font>(<font color="Maroon">D</font> <a href="monoid_0.html#K10" target="_self">*+^</a> )
 
<b>by </b><i/>;<br/>
<b>then reconsider </b><font color="Maroon">p'</font> = <font color="Maroon">p</font>, <font color="Maroon">q'</font> = <font color="Maroon">q</font> as   <a href="struct_0.html#NM1">Element</a> of <span class="p1">(<span class="default"><font color="Maroon">D</font> <a href="monoid_0.html#K10" target="_self">*+^</a> </span>)</span> <b>by </b><i><a class="ref" href="tarski.html#D3">TARSKI:def 3</a></i>;<br/>
<b>thus </b><font color="Maroon">p</font> <a href="monoid_0.html#K2" target="_self">[*]</a> <font color="Maroon">q</font> = 
<font color="Maroon">p'</font> <a href="monoid_0.html#K2" target="_self">[*]</a> <font color="Maroon">q'</font>
<b>by </b><i/>
<br/>.= 
<font color="Maroon">p</font> <a href="finseq_1.html#K7">^</a> <font color="Maroon">q</font>
<b>by </b><i><a class="txt" href="monoid_0.html#E28"><i><font color="Green">Lemma58</font></i></a></i>
;<br/>


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