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<b>let </b><font color="Maroon" title="c1">a</font>, <font color="Maroon" title="c2">b</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> (  <a href="gate_1.html#NR1" title="GATE_1:NR.1">$</a>  <a href="gate_1.html#K5" title="GATE_1:func.5">EQV2</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">b</font> iff not  <a href="gate_1.html#NR1" title="GATE_1:NR.1">$</a>  <a href="gate_1.html#K4" title="GATE_1:func.4">XOR2</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">b</font> )</span><br/>



<a NAME="E1:8"/>
(  <a href="gate_1.html#NR1" title="GATE_1:NR.1">$</a>  <a href="gate_1.html#K5" title="GATE_1:func.5">EQV2</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">b</font> iff (  <a href="gate_1.html#NR1" title="GATE_1:NR.1">$</a> <font color="Maroon" title="c1">a</font> iff  <a href="gate_1.html#NR1" title="GATE_1:NR.1">$</a> <font color="Maroon" title="c2">b</font> ) )
 
<b>by </b><i><a class="ref" href="gate_1.html#D5" target="_self" title="GATE_1:def.5">Def5</a>, <a class="ref" href="gate_1.html#T5" target="_self" title="GATE_1:th.5">Th5</a></i>;<br/>
<b>hence </b><a NAME="E2:8"/>
(  <a href="gate_1.html#NR1" title="GATE_1:NR.1">$</a>  <a href="gate_1.html#K5" title="GATE_1:func.5">EQV2</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">b</font> iff not  <a href="gate_1.html#NR1" title="GATE_1:NR.1">$</a>  <a href="gate_1.html#K4" title="GATE_1:func.4">XOR2</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">b</font> )
 <b>by </b><i><a class="ref" href="gate_1.html#D4" target="_self" title="GATE_1:def.4">Def4</a>, <a class="ref" href="gate_1.html#T5" target="_self" title="GATE_1:th.5">Th5</a></i>; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> verum</span><br/>


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