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<b>let </b><font color="Maroon">G</font> be  <a href="group_1.html#V1">strict</a> <a href="group_1.html#NM1">Group</a>;<br/><b>let </b><font color="Maroon">F2</font> be  <a href="group_1.html#V1">strict</a>  <a href="group_2.html#M1">Subgroup</a> of <font color="Maroon">G</font>;<br/><b>let </b><font color="Maroon">F1</font> be  <a href="group_1.html#V1">strict</a> <a href="group_3.html#V1">normal</a>  <a href="group_6.html#M1">Subgroup</a> of <font color="Maroon">F2</font>;<br/><b>let </b><font color="Maroon">a</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">F2</font>, <font color="Maroon">b</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">F2</font>;<br/>







<a NAME="E1:4"/><i><font color="Green">E37</font></i>: 
<span class="p1">(<span class="default"><a href="group_6.html#K10">nat_hom</a> <font color="Maroon">F1</font></span>)</span> <a href="funct_2.html#K3">.</a> <font color="Maroon">a</font> <a href="hidden.html#R1">=</a> <font color="Maroon">a</font> <a href="group_2.html#K12">*</a> <font color="Maroon">F1</font>
 
<b>by </b><i><a class="ref" href="group_6.html#D9">GROUP_6:def 9</a></i>;<br/>
<a NAME="E2:4"/><i><font color="Green">E38</font></i>: 
<span class="p1">(<span class="default"><a href="group_6.html#K10">nat_hom</a> <font color="Maroon">F1</font></span>)</span> <a href="funct_2.html#K3">.</a> <font color="Maroon">b</font> <a href="hidden.html#R1">=</a> <font color="Maroon">b</font> <a href="group_2.html#K12">*</a> <font color="Maroon">F1</font>
 
<b>by </b><i><a class="ref" href="group_6.html#D9">GROUP_6:def 9</a></i>;<br/>
<a NAME="E3:4"/><i><font color="Green">E39</font></i>: 
 <a href="group_6.html#K7">@</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="group_6.html#K10">nat_hom</a> <font color="Maroon">F1</font></span>)</span> <a href="funct_2.html#K3">.</a> <font color="Maroon">a</font></span>)</span> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><a href="group_6.html#K10">nat_hom</a> <font color="Maroon">F1</font></span>)</span> <a href="funct_2.html#K3">.</a> <font color="Maroon">a</font>
 
<b>by </b><i><a class="ref" href="group_6.html#D6">GROUP_6:def 6</a></i>;<br/>
<a NAME="E4:4"/><i><font color="Green">E40</font></i>: 
 <a href="group_6.html#K7">@</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="group_6.html#K10">nat_hom</a> <font color="Maroon">F1</font></span>)</span> <a href="funct_2.html#K3">.</a> <font color="Maroon">b</font></span>)</span> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><a href="group_6.html#K10">nat_hom</a> <font color="Maroon">F1</font></span>)</span> <a href="funct_2.html#K3">.</a> <font color="Maroon">b</font>
 
<b>by </b><i><a class="ref" href="group_6.html#D6">GROUP_6:def 6</a></i>;<br/>
<b>thus </b><span class="p1">(<span class="default"><font color="Maroon">a</font> <a href="group_1.html#K1">*</a> <font color="Maroon">b</font></span>)</span> <a href="group_2.html#K12">*</a> <font color="Maroon">F1</font> = 
<span class="p1">(<span class="default"><a href="group_6.html#K10">nat_hom</a> <font color="Maroon">F1</font></span>)</span> <a href="funct_2.html#K3">.</a> <span class="p1">(<span class="default"><font color="Maroon">a</font> <a href="group_1.html#K1">*</a> <font color="Maroon">b</font></span>)</span>
<b>by </b><i><a class="ref" href="group_6.html#D9">GROUP_6:def 9</a></i>
<br/>.= 
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="group_6.html#K10">nat_hom</a> <font color="Maroon">F1</font></span>)</span> <a href="funct_2.html#K3">.</a> <font color="Maroon">a</font></span>)</span> <a href="group_1.html#K1">*</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="group_6.html#K10">nat_hom</a> <font color="Maroon">F1</font></span>)</span> <a href="funct_2.html#K3">.</a> <font color="Maroon">b</font></span>)</span>
<b>by </b><i><a class="ref" href="group_6.html#D7">GROUP_6:def 7</a></i>
<br/>.= 
<span class="p1">(<span class="default"><font color="Maroon">a</font> <a href="group_2.html#K12">*</a> <font color="Maroon">F1</font></span>)</span> <a href="group_2.html#K2">*</a> <span class="p1">(<span class="default"><font color="Maroon">b</font> <a href="group_2.html#K12">*</a> <font color="Maroon">F1</font></span>)</span>
<b>by </b><i>, , , , <a class="ref" href="group_6.html#T24">GROUP_6:24</a></i>
;<br/>


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