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<b>consider </b><font color="Maroon" title="c2">x</font> being    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon" title="c1">f</font>;<br/>
<b>consider </b><font color="Maroon" title="c3">x1</font>, <font color="Maroon" title="c4">x2</font> being    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> <b> such that </b><br/><a NAME="E3:60_2_1"/><i><font color="Green" title="E26">A2</font></i>: 
<font color="Maroon" title="c2">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"><a href="tarski.html#K4" title="TARSKI:func.4">[</a><span class="default"><font color="Maroon" title="c3">x1</font>,<font color="Maroon" title="c4">x2</font></span><a href="tarski.html#K4" title="TARSKI:func.4">]</a></span>
 <b>by </b><i><a class="ref" href="relat_1.html#D1" target="_self" title="RELAT_1:def.1">Def1</a></i>;<br/>
<b>thus </b><a NAME="E4:60_2_1"/>
not  <a href="relat_1.html#NK4" title="RELAT_1:NK.4">rng</a> <font color="Maroon" title="c1">f</font> is <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>
 <b>by </b><i><a class="txt" href="relat_1.html#E3:60_2_1"><i><font color="Green" title="E26">A2</font></i></a>, <a class="ref" href="relat_1.html#D5" target="_self" title="RELAT_1:def.5">Def5</a></i>;<br/>


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