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<b>let </b><font color="Maroon">AFV</font> be   <a href="afvect0.html#NM1">WeakAffVect</a>;<br/><b>let </b><font color="Maroon">a</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">AFV</font>;<br/><b>let </b><font color="Maroon">b</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">AFV</font>;<br/><b>let </b><font color="Maroon">c</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">AFV</font>;<br/><b>let </b><font color="Maroon">d</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">AFV</font>;<br/><b>let </b><font color="Maroon">p</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">AFV</font>;<br/>











<div><i><font color="Green">E22</font></i>: <a class="txt" onclick="hs2(this)" href="javascript:()" title="39_1"><b>now </b></a><div class="add"><b>assume </b><a NAME="E1:39_1"/><i><font color="Green">E36</font></i>: 
<font color="Maroon">a</font>,<font color="Maroon">b</font> <a href="analoaf.html#R2">//</a> <font color="Maroon">c</font>,<font color="Maroon">d</font>
 ;<br/><a NAME="E2:39_1"/><i><font color="Green">E38</font></i>: 
( <font color="Maroon">a</font>,<font color="Maroon">b</font> <a href="analoaf.html#R2">//</a>  <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">b</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">a</font> &amp; <font color="Maroon">c</font>,<font color="Maroon">d</font> <a href="analoaf.html#R2">//</a>  <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">d</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">c</font> )
 <b>by </b><i/>;<br/><a NAME="E3:39_1"/><b>then </b>
 <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">d</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">c</font> <a href="analoaf.html#R2">//</a> <font color="Maroon">c</font>,<font color="Maroon">d</font>
 <b>by </b><i/>;<br/><a NAME="E4:39_1"/><b>then </b><i><font color="Green">E40</font></i>: 
 <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">d</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">c</font> <a href="analoaf.html#R2">//</a> <font color="Maroon">a</font>,<font color="Maroon">b</font>
 <b>by </b><i>, </i>;<br/><a NAME="E5:39_1"/>
 <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">b</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">a</font> <a href="analoaf.html#R2">//</a> <font color="Maroon">a</font>,<font color="Maroon">b</font>
 <b>by </b><i>, </i>;<br/><a NAME="E6:39_1"/><b>then </b>
 <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">b</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">a</font> <a href="analoaf.html#R2">//</a>  <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">d</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">c</font>
 <b>by </b><i>, </i>;<br/><b>hence </b><a NAME="E7:39_1"/>
 <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">a</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">b</font> <a href="analoaf.html#R2">//</a>  <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">c</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">d</font>
 <b>by </b><i/>;<br/></div><b>end;</b></div>
<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="39_2"><b>now </b></a><div class="add"><b>assume </b><a NAME="E1:39_2"/><i><font color="Green">E41</font></i>: 
 <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">a</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">b</font> <a href="analoaf.html#R2">//</a>  <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">c</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">d</font>
 ;<br/><a NAME="E2:39_2"/><i><font color="Green">E42</font></i>: 
( <font color="Maroon">a</font>,<font color="Maroon">b</font> <a href="analoaf.html#R2">//</a>  <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">b</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">a</font> &amp; <font color="Maroon">c</font>,<font color="Maroon">d</font> <a href="analoaf.html#R2">//</a>  <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">d</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">c</font> )
 <b>by </b><i/>;<br/><a NAME="E3:39_2"/>
<font color="Maroon">d</font>,<font color="Maroon">c</font> <a href="analoaf.html#R2">//</a>  <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">c</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">d</font>
 <b>by </b><i/>;<br/><a NAME="E4:39_2"/><b>then </b>
<font color="Maroon">d</font>,<font color="Maroon">c</font> <a href="analoaf.html#R2">//</a>  <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">a</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">b</font>
 <b>by </b><i>, </i>;<br/><a NAME="E5:39_2"/><b>then </b>
<font color="Maroon">c</font>,<font color="Maroon">d</font> <a href="analoaf.html#R2">//</a>  <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">b</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">a</font>
 <b>by </b><i/>;<br/><b>hence </b><a NAME="E6:39_2"/>
<font color="Maroon">a</font>,<font color="Maroon">b</font> <a href="analoaf.html#R2">//</a> <font color="Maroon">c</font>,<font color="Maroon">d</font>
 <b>by </b><i>, </i>;<br/></div><b>end;</b></div>
<b>hence </b><a NAME="E3:39"/>
( <font color="Maroon">a</font>,<font color="Maroon">b</font> <a href="analoaf.html#R2">//</a> <font color="Maroon">c</font>,<font color="Maroon">d</font> iff  <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">a</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">b</font> <a href="analoaf.html#R2">//</a>  <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">c</font>, <a href="afvect0.html#K1" target="_self">PSym</a> <font color="Maroon">p</font>,<font color="Maroon">d</font> )
 <b>by </b><i/>;<br/>


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