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<b>let </b><font color="Maroon">c<sub>2</sub></font> be   <a href="rat_1.html#NM1">Rational</a>;<br/>

<a NAME="E1:44"/><i><font color="Green">E28</font></i>: 
 <a href="rat_1.html#K1" target="_self">denominator</a> <font color="Maroon">c<sub>2</sub></font> <a href="hidden.html#NR2" target="_self">&lt;&gt;</a> 0
 
<b>by </b><i><a class="ref" href="rat_1.html#D3" target="_self">Def3</a></i>;<br/>
<div><i><font color="Green">E29</font></i>: <a class="txt" onclick="hs2(this)" href="javascript:()" title="44_1"><b>now </b></a><div class="add"><b>assume </b><a NAME="E1:44_1"/>
 <a href="rat_1.html#K2" target="_self">numerator</a> <font color="Maroon">c<sub>2</sub></font> <a href="hidden.html#R1">=</a>  <a href="rat_1.html#K1" target="_self">denominator</a> <font color="Maroon">c<sub>2</sub></font>
 ;<br/><a NAME="E2:44_1"/><b>then </b>
<span class="p1">(<span class="default"><a href="rat_1.html#K2" target="_self">numerator</a> <font color="Maroon">c<sub>2</sub></font></span>)</span> <a href="xcmplx_0.html#K7">/</a> <span class="p1">(<span class="default"><a href="rat_1.html#K1" target="_self">denominator</a> <font color="Maroon">c<sub>2</sub></font></span>)</span> <a href="hidden.html#R1">=</a> 1
 <b>by </b><i><a class="txt" href="rat_1.html#E1:44"><i><font color="Green">E28</font></i></a>, <a class="ref" href="xcmplx_1.html#T60">XCMPLX_1:60</a></i>;<br/><b>hence </b><a NAME="E3:44_1"/>
<font color="Maroon">c<sub>2</sub></font> <a href="hidden.html#R1">=</a> 1
 <b>by </b><i><a class="ref" href="rat_1.html#T37" target="_self">Th37</a></i>;<br/></div><b>end;</b></div>
<b>thus </b><a NAME="E3:44"/>
(  <a href="rat_1.html#K2" target="_self">numerator</a> <font color="Maroon">c<sub>2</sub></font> <a href="hidden.html#R1">=</a>  <a href="rat_1.html#K1" target="_self">denominator</a> <font color="Maroon">c<sub>2</sub></font> iff <font color="Maroon">c<sub>2</sub></font> <a href="hidden.html#R1">=</a> 1 )
 <b>by </b><i><a class="txt" href="rat_1.html#E2:44"><i><font color="Green">E29</font></i></a></i>;<br/>


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