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<b>let </b><font color="Maroon">G</font> be   <a href="group_1.html#NM1">Group</a>;<br/><b>let </b><font color="Maroon">a</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">G</font>;<br/><b>let </b><font color="Maroon">b</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">G</font>;<br/><b>let </b><font color="Maroon">N</font> be  <a href="group_1.html#V1">strict</a> <a href="group_3.html#V1">normal</a>  <a href="group_2.html#M1">Subgroup</a> of <font color="Maroon">G</font>;<br/>







<b>assume </b><a NAME="E1:4"/>
<font color="Maroon">a</font> <a href="rlvect_1.html#R1">in</a> <font color="Maroon">N</font>
 ;<br/>

<a NAME="E2:4"/><b>then </b>
<font color="Maroon">a</font> <a href="group_3.html#K2">|^</a> <font color="Maroon">b</font> <a href="rlvect_1.html#R1">in</a> <font color="Maroon">N</font> <a href="group_3.html#K6">|^</a> <font color="Maroon">b</font>
 
<b>by </b><i><a class="ref" href="group_3.html#T70">GROUP_3:70</a></i>;<br/>
<b>hence </b><a NAME="E3:4"/>
<font color="Maroon">a</font> <a href="group_3.html#K2">|^</a> <font color="Maroon">b</font> <a href="rlvect_1.html#R1">in</a> <font color="Maroon">N</font>
 <b>by </b><i><a class="ref" href="group_3.html#D13">GROUP_3:def 13</a></i>;<br/>


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