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<b>let </b><font color="Maroon" title="c1">F</font> be  <a href="fraenkel.html#V1" title="FRAENKEL:attr.1">functional</a>  <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ;<br/><b>let </b><font color="Maroon" title="c2">B</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ;<br/>



<b>assume </b><a NAME="E1:44"/><i><font color="Green" title="E11">A1</font></i>: 
<font color="Maroon" title="c2">B</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a> <font color="Maroon" title="c1">F</font>
 ;<br/>

<b>let </b><font color="Maroon" title="c3">x</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ; <i><font color="Red">:: according to </font></i><a class="ref" href="fraenkel.html#D1" target="_self" title="FRAENKEL:def.1">FRAENKEL:def 1</a><br/>

<b>assume </b><a NAME="E2:44"/>
<font color="Maroon" title="c3">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c2">B</font>
 ;<br/>

<a NAME="E3:44"/><b>then </b>
<font color="Maroon" title="c3">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c1">F</font>
 
<b>by </b><i><a class="txt" href="fraenkel.html#E1:44"><i><font color="Green" title="E11">A1</font></i></a></i>;<br/>
<b>hence </b><a NAME="E4:44"/>
<font color="Maroon" title="c3">x</font> is   <a href="funct_1.html#NM1" title="FUNCT_1:NM.1">Function</a>
 <b>by </b><i><a class="ref" href="fraenkel.html#D1" target="_self" title="FRAENKEL:def.1">Def1</a></i>;<br/>


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