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<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="54_1_2_1"><b>now </b></a><div class="add"><b>let </b><font color="Maroon">z1</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">R</font>;<br/><b>assume </b><a NAME="E1:54_1_2_1"/><i><font color="Green">E61</font></i>: 
( <font color="Maroon">z1</font> <a href="hidden.html#R2">in</a> <font color="Maroon">Amp</font> &amp; <font color="Maroon">z1</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">x</font> &amp; <font color="Maroon">z1</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">y</font> &amp; ( for <font color="Olive">z</font> being  <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">R</font>  st <font color="Olive">z</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">x</font> &amp; <font color="Olive">z</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">y</font> holds <br/><font color="Olive">z</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">z1</font> ) )
 ;<br/><b>let </b><font color="Maroon">z2</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">R</font>;<br/><b>assume </b><a NAME="E2:54_1_2_1"/><i><font color="Green">E62</font></i>: 
( <font color="Maroon">z2</font> <a href="hidden.html#R2">in</a> <font color="Maroon">Amp</font> &amp; <font color="Maroon">z2</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">x</font> &amp; <font color="Maroon">z2</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">y</font> &amp; ( for <font color="Olive">z</font> being  <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">R</font>  st <font color="Olive">z</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">x</font> &amp; <font color="Olive">z</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">y</font> holds <br/><font color="Olive">z</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">z2</font> ) )
 ;<br/><a NAME="E3:54_1_2_1"/>
<font color="Maroon">z1</font> <a href="gcd_1.html#R4" target="_self">is_associated_to</a> <font color="Maroon">z2</font>
 <div><a class="txt" onclick="hs2(this)" href="javascript:()" title="54_1_2_1_1"><b>proof </b></a><div class="add">

<a NAME="E1:54_1_2_1_1"/><i><font color="Green">E63</font></i>: 
<font color="Maroon">z1</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">z2</font>
 
<b>by </b><i><a class="ref" href="gcd_1.html#D2" target="_self">Def2</a>, <a class="ref" href="gcd_1.html#D3" target="_self">Def3</a></i>;<br/>
<a NAME="E2:54_1_2_1_1"/>
<font color="Maroon">z2</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">z1</font>
 
<b>by </b><i><a class="ref" href="gcd_1.html#D2" target="_self">Def2</a>, <a class="ref" href="gcd_1.html#D3" target="_self">Def3</a></i>;<br/>
<b>hence </b><a NAME="E3:54_1_2_1_1"/>
<font color="Maroon">z1</font> <a href="gcd_1.html#R4" target="_self">is_associated_to</a> <font color="Maroon">z2</font>
 <b>by </b><i><a class="ref" href="gcd_1.html#D4" target="_self">Def4</a>, </i>;<br/>


</div><b>end;</b></div><b>hence </b><a NAME="E4:54_1_2_1"/>
<font color="Maroon">z1</font> <a href="hidden.html#R1">=</a> <font color="Maroon">z2</font>
 <b>by </b><i><a class="ref" href="gcd_1.html#D2" target="_self">Def2</a>, <a class="ref" href="gcd_1.html#D3" target="_self">Def3</a>, </i>;<br/></div><b>end;</b></div>
<b>hence </b><a NAME="E2:54_1_2"/>
for <font color="Olive">b<sub>1</sub></font>, <font color="Olive">b<sub>2</sub></font> being  <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">R</font>  st <font color="Olive">b<sub>1</sub></font> <a href="hidden.html#R2">in</a> <font color="Maroon">Amp</font> &amp; <font color="Olive">b<sub>1</sub></font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">x</font> &amp; <font color="Olive">b<sub>1</sub></font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">y</font> &amp; ( for <font color="Olive">z</font> being  <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">R</font>  st <font color="Olive">z</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">x</font> &amp; <font color="Olive">z</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">y</font> holds <br/><font color="Olive">z</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Olive">b<sub>1</sub></font> ) &amp; <font color="Olive">b<sub>2</sub></font> <a href="hidden.html#R2">in</a> <font color="Maroon">Amp</font> &amp; <font color="Olive">b<sub>2</sub></font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">x</font> &amp; <font color="Olive">b<sub>2</sub></font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">y</font> &amp; ( for <font color="Olive">z</font> being  <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">R</font>  st <font color="Olive">z</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">x</font> &amp; <font color="Olive">z</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Maroon">y</font> holds <br/><font color="Olive">z</font> <a href="gcd_1.html#R2" target="_self">divides</a> <font color="Olive">b<sub>2</sub></font> ) holds <br/><font color="Olive">b<sub>1</sub></font> <a href="hidden.html#R1">=</a> <font color="Olive">b<sub>2</sub></font>
 ;<br/>


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