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<b>let </b><font color="Maroon">c<sub>1</sub></font> be   <a href="group_1.html#NM1">Group</a>;<br/><b>let </b><font color="Maroon">c<sub>2</sub></font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">c<sub>1</sub></font>;<br/>



<b>assume </b><a NAME="E1:73"/><i><font color="Green">E58</font></i>: 
 <a href="group_1.html#K7" target="_self">ord</a> <font color="Maroon">c<sub>2</sub></font> <a href="hidden.html#R1">=</a> 1
 ;<br/>

<a NAME="E2:73"/><b>then </b>
not <font color="Maroon">c<sub>2</sub></font> <a href="group_1.html#NR2" target="_self">is_of_order_0</a> 
 
<b>by </b><i><a class="ref" href="group_1.html#D12" target="_self">Def12</a></i>;<br/>
<a NAME="E3:73"/><b>then </b>
<font color="Maroon">c<sub>2</sub></font> <a href="group_1.html#K6" target="_self">|^</a> 1 <a href="hidden.html#R1">=</a>  <a href="group_1.html#K2" target="_self">1.</a> <font color="Maroon">c<sub>1</sub></font>
 
<b>by </b><i><a class="txt" href="group_1.html#E1:73"><i><font color="Green">E58</font></i></a>, <a class="ref" href="group_1.html#D12" target="_self">Def12</a></i>;<br/>
<b>hence </b><a NAME="E4:73"/>
<font color="Maroon">c<sub>2</sub></font> <a href="hidden.html#R1">=</a>  <a href="group_1.html#K2" target="_self">1.</a> <font color="Maroon">c<sub>1</sub></font>
 <b>by </b><i><a class="ref" href="group_1.html#T44" target="_self">Th44</a></i>;<br/>


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