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<b>let </b><font color="Maroon">a</font> be    <a href="hidden.html#M1">set</a> , <font color="Maroon">b</font> be    <a href="hidden.html#M1">set</a> ;<br/>

<a NAME="E1:1"/>
( (  not  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K10">XOR3</a> <font color="Maroon">a</font>,<font color="Maroon">b</font>,<a href="xboole_0.html#K1">{}</a>  or (  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">a</font> &amp; not  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">b</font> ) or ( not  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">a</font> &amp;  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">b</font> ) ) &amp; ( ( (  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">a</font> &amp; not  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">b</font> ) or ( not  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">a</font> &amp;  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">b</font> ) ) implies  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K10">XOR3</a> <font color="Maroon">a</font>,<font color="Maroon">b</font>,<a href="xboole_0.html#K1">{}</a>  ) &amp; (  not  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K10">XOR3</a> <font color="Maroon">a</font>,<a href="xboole_0.html#K1">{}</a> ,<font color="Maroon">b</font> or (  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">a</font> &amp; not  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">b</font> ) or ( not  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">a</font> &amp;  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">b</font> ) ) &amp; ( ( (  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">a</font> &amp; not  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">b</font> ) or ( not  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">a</font> &amp;  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">b</font> ) ) implies  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K10">XOR3</a> <font color="Maroon">a</font>,<a href="xboole_0.html#K1">{}</a> ,<font color="Maroon">b</font> ) &amp; (  not  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K10">XOR3</a> <a href="xboole_0.html#K1">{}</a> ,<font color="Maroon">a</font>,<font color="Maroon">b</font> or (  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">a</font> &amp; not  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">b</font> ) or ( not  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">a</font> &amp;  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">b</font> ) ) &amp; ( ( (  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">a</font> &amp; not  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">b</font> ) or ( not  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">a</font> &amp;  <a href="gate_1.html#NR1" target="_self">$</a> <font color="Maroon">b</font> ) ) implies  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K10">XOR3</a> <a href="xboole_0.html#K1">{}</a> ,<font color="Maroon">a</font>,<font color="Maroon">b</font> ) )
 
<b>by </b><i><a class="ref" href="gate_1.html#T18">GATE_1:18</a></i>;<br/>
<b>hence </b><a NAME="E2:1"/>
( (  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K10">XOR3</a> <font color="Maroon">a</font>,<font color="Maroon">b</font>,<a href="xboole_0.html#K1">{}</a>  implies  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K4">XOR2</a> <font color="Maroon">a</font>,<font color="Maroon">b</font> ) &amp; (  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K4">XOR2</a> <font color="Maroon">a</font>,<font color="Maroon">b</font> implies  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K10">XOR3</a> <font color="Maroon">a</font>,<font color="Maroon">b</font>,<a href="xboole_0.html#K1">{}</a>  ) &amp; (  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K10">XOR3</a> <font color="Maroon">a</font>,<a href="xboole_0.html#K1">{}</a> ,<font color="Maroon">b</font> implies  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K4">XOR2</a> <font color="Maroon">a</font>,<font color="Maroon">b</font> ) &amp; (  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K4">XOR2</a> <font color="Maroon">a</font>,<font color="Maroon">b</font> implies  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K10">XOR3</a> <font color="Maroon">a</font>,<a href="xboole_0.html#K1">{}</a> ,<font color="Maroon">b</font> ) &amp; (  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K10">XOR3</a> <a href="xboole_0.html#K1">{}</a> ,<font color="Maroon">a</font>,<font color="Maroon">b</font> implies  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K4">XOR2</a> <font color="Maroon">a</font>,<font color="Maroon">b</font> ) &amp; (  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K4">XOR2</a> <font color="Maroon">a</font>,<font color="Maroon">b</font> implies  <a href="gate_1.html#NR1" target="_self">$</a>  <a href="gate_1.html#K10">XOR3</a> <a href="xboole_0.html#K1">{}</a> ,<font color="Maroon">a</font>,<font color="Maroon">b</font> ) )
 <b>by </b><i><a class="ref" href="gate_1.html#T8">GATE_1:8</a></i>;<br/>


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