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<b>let </b><font color="Maroon">f</font> be   <a href="funct_1.html#NM1">Function</a>;<br/><b>let </b><font color="Maroon">g</font> be   <a href="funct_1.html#NM1">Function</a>;<br/><b>let </b><font color="Maroon">A</font> be    <a href="hidden.html#M1">set</a> ;<br/><b>let </b><font color="Maroon">F</font> be   <a href="funct_1.html#NM1">Function</a>;<br/><b>let </b><font color="Maroon">x</font> be    <a href="hidden.html#M1">set</a> ;<br/>









<b>assume </b><a NAME="E1:43"/><i><font color="Green">E12</font></i>: 
<font color="Maroon">f</font> <a href="relat_1.html#K7">|</a> <font color="Maroon">A</font> <a href="hidden.html#R1">=</a> <font color="Maroon">g</font> <a href="relat_1.html#K7">|</a> <font color="Maroon">A</font>
 ;<br/>

<span class="p1">(<span class="default"><a href="relat_1.html#K1">dom</a> <font color="Maroon">f</font></span>)</span> <a href="xboole_0.html#K3">/\</a> <font color="Maroon">A</font> = 
 <a href="relat_1.html#K1">dom</a> <span class="p1">(<span class="default"><font color="Maroon">f</font> <a href="relat_1.html#K7">|</a> <font color="Maroon">A</font></span>)</span>
<b>by </b><i><a class="ref" href="relat_1.html#T90">RELAT_1:90</a></i>
<br/>.= 
<span class="p1">(<span class="default"><a href="relat_1.html#K1">dom</a> <font color="Maroon">g</font></span>)</span> <a href="xboole_0.html#K3">/\</a> <font color="Maroon">A</font>
<b>by </b><i>, <a class="ref" href="relat_1.html#T90">RELAT_1:90</a></i>
;<br/>
<b>then </b><i><font color="Green">E13</font></i>: <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="relat_1.html#K1">dom</a> <font color="Maroon">f</font></span>)</span> <a href="funcop_1.html#K2" target="_self">--&gt;</a> <font color="Maroon">x</font></span>)</span> <a href="relat_1.html#K7">|</a> <font color="Maroon">A</font> = 
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="relat_1.html#K1">dom</a> <font color="Maroon">g</font></span>)</span> <a href="xboole_0.html#K3">/\</a> <font color="Maroon">A</font></span>)</span> <a href="funcop_1.html#K2" target="_self">--&gt;</a> <font color="Maroon">x</font>
<b>by </b><i><a class="txt" href="funcop_1.html#E3:43"><i><font color="Green">E13</font></i></a></i>
<br/>.= 
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="relat_1.html#K1">dom</a> <font color="Maroon">g</font></span>)</span> <a href="funcop_1.html#K2" target="_self">--&gt;</a> <font color="Maroon">x</font></span>)</span> <a href="relat_1.html#K7">|</a> <font color="Maroon">A</font>
<b>by </b><i><a class="txt" href="funcop_1.html#E3:43"><i><font color="Green">E13</font></i></a></i>
;<br/>
<b>thus </b><span class="p1">(<span class="default"><font color="Maroon">F</font> <a href="funcop_1.html#K5" target="_self">[;]</a> <font color="Maroon">x</font>,<font color="Maroon">f</font></span>)</span> <a href="relat_1.html#K7">|</a> <font color="Maroon">A</font> = 
<span class="p1">(<span class="default"><font color="Maroon">F</font> <a href="funcop_1.html#K3" target="_self">.:</a> <span class="p2">(<span class="default"><span class="p3">(<span class="default"><a href="relat_1.html#K1">dom</a> <font color="Maroon">f</font></span>)</span> <a href="funcop_1.html#K2" target="_self">--&gt;</a> <font color="Maroon">x</font></span>)</span>,<font color="Maroon">f</font></span>)</span> <a href="relat_1.html#K7">|</a> <font color="Maroon">A</font>

<br/>.= 
<span class="p1">(<span class="default"><font color="Maroon">F</font> <a href="funcop_1.html#K3" target="_self">.:</a> <span class="p2">(<span class="default"><span class="p3">(<span class="default"><a href="relat_1.html#K1">dom</a> <font color="Maroon">f</font></span>)</span> <a href="funcop_1.html#K2" target="_self">--&gt;</a> <font color="Maroon">x</font></span>)</span>,<font color="Maroon">g</font></span>)</span> <a href="relat_1.html#K7">|</a> <font color="Maroon">A</font>
<b>by </b><i>, </i>
<br/>.= 
<span class="p1">(<span class="default"><font color="Maroon">F</font> <a href="funcop_1.html#K3" target="_self">.:</a> <span class="p2">(<span class="default"><span class="p3">(<span class="default"><a href="relat_1.html#K1">dom</a> <font color="Maroon">g</font></span>)</span> <a href="funcop_1.html#K2" target="_self">--&gt;</a> <font color="Maroon">x</font></span>)</span>,<font color="Maroon">g</font></span>)</span> <a href="relat_1.html#K7">|</a> <font color="Maroon">A</font>
<b>by </b><i>, </i>
<br/>.= 
<span class="p1">(<span class="default"><font color="Maroon">F</font> <a href="funcop_1.html#K5" target="_self">[;]</a> <font color="Maroon">x</font>,<font color="Maroon">g</font></span>)</span> <a href="relat_1.html#K7">|</a> <font color="Maroon">A</font>

;<br/>


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