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<b>let </b><font color="Maroon">f1</font> be   <a href="funct_1.html#NM1">Function</a>, <font color="Maroon">f2</font> be   <a href="funct_1.html#NM1">Function</a>;<br/>

<b>assume </b><b>that </b><br/><a NAME="E1:54_1_2"/><i><font color="Green">E38</font></i>: 
 <a href="relat_1.html#K1">dom</a> <font color="Maroon">f1</font> <a href="hidden.html#R1">=</a>  <a href="funct_2.html#K1">Funcs</a> <font color="Maroon">P</font>,<a href="numbers.html#K5">NAT</a> 
 <b>and </b><br/><a NAME="E2:54_1_2"/><i><font color="Green">E41</font></i>: 
for <font color="Olive">m</font> being   <a href="pnproc_1.html#M1" target="_self">marking</a> of <font color="Maroon">P</font> holds  <font color="Maroon">f1</font> <a href="funct_1.html#K1">.</a> <font color="Olive">m</font> <a href="hidden.html#R1">=</a>  <a href="pnproc_1.html#K8" target="_self">fire</a> <font color="Maroon">t</font>,<font color="Olive">m</font>
 <b>and </b><br/><a NAME="E3:54_1_2"/><i><font color="Green">E43</font></i>: 
 <a href="relat_1.html#K1">dom</a> <font color="Maroon">f2</font> <a href="hidden.html#R1">=</a>  <a href="funct_2.html#K1">Funcs</a> <font color="Maroon">P</font>,<a href="numbers.html#K5">NAT</a> 
 <b>and </b><br/><a NAME="E4:54_1_2"/><i><font color="Green">E45</font></i>: 
for <font color="Olive">m</font> being   <a href="pnproc_1.html#M1" target="_self">marking</a> of <font color="Maroon">P</font> holds  <font color="Maroon">f2</font> <a href="funct_1.html#K1">.</a> <font color="Olive">m</font> <a href="hidden.html#R1">=</a>  <a href="pnproc_1.html#K8" target="_self">fire</a> <font color="Maroon">t</font>,<font color="Olive">m</font>
 ;<br/>

<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="54_1_2_1"><b>now </b></a><div class="add"><b>let </b><font color="Maroon">x</font> be    <a href="hidden.html#M1">set</a> ;<br/><b>assume </b><a NAME="E1:54_1_2_1"/>
<font color="Maroon">x</font> <a href="hidden.html#R2">in</a>  <a href="relat_1.html#K1">dom</a> <font color="Maroon">f1</font>
 ;<br/><b>then reconsider </b><font color="Maroon">m</font> = <font color="Maroon">x</font> as    <a href="pnproc_1.html#M1" target="_self">marking</a> of <font color="Maroon">P</font> <b>by </b><i>, </i>;<br/><b>thus </b><font color="Maroon">f1</font> <a href="funct_1.html#K1">.</a> <font color="Maroon">x</font> = 
 <a href="pnproc_1.html#K8" target="_self">fire</a> <font color="Maroon">t</font>,<font color="Maroon">m</font>
<b>by </b><i><a class="txt" href="pnproc_1.html#E1:54_1_2"><i><font color="Green">E38</font></i></a></i>
<br/>.= 
<font color="Maroon">f2</font> <a href="funct_1.html#K1">.</a> <font color="Maroon">x</font>
<b>by </b><i><a class="ref" href="pnproc_1.html#T4" target="_self">Th4</a></i>
;<br/></div><b>end;</b></div>
<b>hence </b><a NAME="E6:54_1_2"/>
<font color="Maroon">f1</font> <a href="hidden.html#R1">=</a> <font color="Maroon">f2</font>
 <b>by </b><i>, , <a class="ref" href="funct_1.html#T9">FUNCT_1:9</a></i>;<br/>


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