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<b>let </b><font color="Maroon">t</font> be    <a href="nattra_1.html#M1" target="_self">transformation</a> of <font color="Maroon">F2</font>,<font color="Maroon">F1</font>, <font color="Maroon">t'</font> be    <a href="nattra_1.html#M1" target="_self">transformation</a> of <font color="Maroon">F2</font>,<font color="Maroon">F1</font>;<br/>

<b>assume </b><b>that </b><br/><a NAME="E1:46_1_2"/><i><font color="Green">E27</font></i>: 
for <font color="Olive">a</font> being  <a href="cat_1.html#NM1">Object</a> of <font color="Maroon">A</font> holds  <font color="Maroon">t</font> <a href="nattra_1.html#K5" target="_self">.</a> <font color="Olive">a</font> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><font color="Maroon">t1</font> <a href="nattra_1.html#K5" target="_self">.</a> <font color="Olive">a</font></span>)</span> <a href="cat_1.html#K11">"</a> 
 <b>and </b><br/><a NAME="E2:46_1_2"/><i><font color="Green">E33</font></i>: 
for <font color="Olive">a</font> being  <a href="cat_1.html#NM1">Object</a> of <font color="Maroon">A</font> holds  <font color="Maroon">t'</font> <a href="nattra_1.html#K5" target="_self">.</a> <font color="Olive">a</font> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><font color="Maroon">t1</font> <a href="nattra_1.html#K5" target="_self">.</a> <font color="Olive">a</font></span>)</span> <a href="cat_1.html#K11">"</a> 
 ;<br/>

<a NAME="E3:46_1_2"/><i><font color="Green">E34</font></i>: 
<font color="Maroon">F2</font> <a href="nattra_1.html#R1" target="_self">is_transformable_to</a> <font color="Maroon">F1</font>
 
<b>by </b><i>, , </i>;<br/>
<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="46_1_2_1"><b>now </b></a><div class="add"><b>let </b><font color="Maroon">a</font> be   <a href="cat_1.html#NM1">Object</a> of <font color="Maroon">A</font>;<br/><b>thus </b><font color="Maroon">t</font> <a href="nattra_1.html#K5" target="_self">.</a> <font color="Maroon">a</font> = 
<span class="p1">(<span class="default"><font color="Maroon">t1</font> <a href="nattra_1.html#K5" target="_self">.</a> <font color="Maroon">a</font></span>)</span> <a href="cat_1.html#K11">"</a> 
<b>by </b><i/>
<br/>.= 
<font color="Maroon">t'</font> <a href="nattra_1.html#K5" target="_self">.</a> <font color="Maroon">a</font>
<b>by </b><i/>
;<br/></div><b>end;</b></div>
<b>hence </b><a NAME="E5:46_1_2"/>
<font color="Maroon">t</font> <a href="hidden.html#R1">=</a> <font color="Maroon">t'</font>
 <b>by </b><i>, <a class="ref" href="nattra_1.html#T2" target="_self">Th2</a></i>;<br/>


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