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<b>let </b><font color="Maroon">x1</font> be   <a href="zf_lang.html#NM1">Variable</a>;<br/><b>let </b><font color="Maroon">x2</font> be   <a href="zf_lang.html#NM1">Variable</a>;<br/><b>let </b><font color="Maroon">x3</font> be   <a href="zf_lang.html#NM1">Variable</a>;<br/><b>let </b><font color="Maroon">x4</font> be   <a href="zf_lang.html#NM1">Variable</a>;<br/><b>let </b><font color="Maroon">M</font> be  non <a href="xboole_0.html#V1">empty</a>  <a href="hidden.html#M1">set</a> ;<br/><b>let </b><font color="Maroon">m1</font> be    <a href="subset_1.html#M1">Element</a> of <font color="Maroon">M</font>;<br/><b>let </b><font color="Maroon">m2</font> be    <a href="subset_1.html#M1">Element</a> of <font color="Maroon">M</font>;<br/><b>let </b><font color="Maroon">m</font> be    <a href="subset_1.html#M1">Element</a> of <font color="Maroon">M</font>;<br/><b>let </b><font color="Maroon">m3</font> be    <a href="subset_1.html#M1">Element</a> of <font color="Maroon">M</font>;<br/><b>let </b><font color="Maroon">m4</font> be    <a href="subset_1.html#M1">Element</a> of <font color="Maroon">M</font>;<br/><b>let </b><font color="Maroon">v</font> be   <a href="funct_2.html#NM1">Function</a> of  <a href="zf_lang.html#K1">VAR</a> ,<font color="Maroon">M</font>;<br/>





















<a NAME="E1:9"/><i><font color="Green">E46</font></i>: 
( <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m1</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> <a href="funct_2.html#R2">=</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m1</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> or <font color="Maroon">x1</font> <a href="hidden.html#R1">=</a> <font color="Maroon">x2</font> )
 
<b>by </b><i><a class="ref" href="zf_lang1.html#T79">ZF_LANG1:79</a></i>;<br/>
<b>hence </b><a NAME="E2:9"/>
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m1</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> <a href="funct_2.html#R2">=</a> <span class="p1">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font>
 <b>by </b><i><a class="ref" href="zf_lang1.html#T78">ZF_LANG1:78</a></i>;<br/>

<a NAME="E3:9"/>
( <font color="Maroon">x1</font> <a href="hidden.html#R1">=</a> <font color="Maroon">x3</font> or <font color="Maroon">x1</font> <a href="hidden.html#NR2" target="_self">&lt;&gt;</a> <font color="Maroon">x3</font> )
 
;<br/>
<a NAME="E4:9"/><b>then </b><i><font color="Green">E47</font></i>: 
( ( <span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m1</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> <a href="funct_2.html#R2">=</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m1</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font> &amp; <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> <a href="funct_2.html#R2">=</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font> ) or ( <span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m1</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> <a href="funct_2.html#R2">=</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m1</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> &amp; <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> <a href="funct_2.html#R2">=</a> <span class="p1">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> ) )
 
<b>by </b><i><a class="ref" href="zf_lang1.html#T78">ZF_LANG1:78</a>, <a class="ref" href="zf_lang1.html#T79">ZF_LANG1:79</a></i>;<br/>
<b>hence </b><a NAME="E5:9"/>
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m1</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> <a href="funct_2.html#R2">=</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font>
 <b>by </b><i>, <a class="ref" href="zf_lang1.html#T78">ZF_LANG1:78</a></i>;<br/>

<a NAME="E6:9"/>
( <font color="Maroon">x1</font> <a href="hidden.html#R1">=</a> <font color="Maroon">x4</font> or <font color="Maroon">x1</font> <a href="hidden.html#NR2" target="_self">&lt;&gt;</a> <font color="Maroon">x4</font> )
 
;<br/>
<a NAME="E7:9"/><b>then </b>
( ( <span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><span class="p4">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m1</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x4</font>,<font color="Maroon">m4</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> <a href="funct_2.html#R2">=</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><span class="p4">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m1</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x4</font>,<font color="Maroon">m4</font> &amp; <span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x4</font>,<font color="Maroon">m4</font> <a href="funct_2.html#R2">=</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x4</font>,<font color="Maroon">m4</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> ) or ( <span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><span class="p4">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m1</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x4</font>,<font color="Maroon">m4</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> <a href="funct_2.html#R2">=</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m1</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> &amp; <span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x4</font>,<font color="Maroon">m4</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> <a href="funct_2.html#R2">=</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> ) )
 
<b>by </b><i><a class="ref" href="zf_lang1.html#T78">ZF_LANG1:78</a>, <a class="ref" href="zf_lang1.html#T79">ZF_LANG1:79</a></i>;<br/>
<b>hence </b><a NAME="E8:9"/>
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><span class="p4">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m1</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x4</font>,<font color="Maroon">m4</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font> <a href="funct_2.html#R2">=</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><font color="Maroon">v</font> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x2</font>,<font color="Maroon">m2</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x3</font>,<font color="Maroon">m3</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x4</font>,<font color="Maroon">m4</font></span>)</span> <a href="zf_lang1.html#K1">/</a> <font color="Maroon">x1</font>,<font color="Maroon">m</font>
 <b>by </b><i>, , <a class="ref" href="zf_lang1.html#T78">ZF_LANG1:78</a></i>;<br/>


</div>
