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<span class="kw">let </span><font color="Maroon" title="c1">R</font> be   <a href="group_1.html#V5" title="GROUP_1:attr.5">commutative</a>  <a href="vectsp_1.html#NM3" title="VECTSP_1:NM.3">Ring</a>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide">  for <font color="Olive" title="b1">S</font> being   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="c0sp1.html#V3" title="C0SP1:attr.3">multiplicatively-closed</a>  <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c1">R</font><br/>  for <font color="Olive" title="b2">a</font> being    <a href="subset_1.html#M2" title="SUBSET_1:mode.2">Element</a> of  <a href="ringfrac.html#K6" title="RINGFRAC:func.6">Frac</a> <font color="Olive" title="b1">S</font>  st <font color="Olive" title="b2">a</font> <a href="domain_1.html#K2" title="DOMAIN_1:func.2">`1</a>  <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b2">a</font> <a href="domain_1.html#K3" title="DOMAIN_1:func.3">`2</a>  holds <br/> <a href="eqrel_1.html#K6" title="EQREL_1:func.6">Class</a> (<span class="p1">(<span class="default"><a href="ringfrac.html#K12" title="RINGFRAC:func.12">EqRel</a> <font color="Olive" title="b1">S</font></span>)</span>,<font color="Olive" title="b2">a</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <span class="p1">(<span class="default"><font color="Olive" title="b1">S</font> <a href="ringfrac.html#NK17" title="RINGFRAC:NK.17">~</a> <font color="Maroon" title="c1">R</font></span>)</span></span><br/><span class="kw">let </span><font color="Maroon" title="c2">S</font> be   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="c0sp1.html#V3" title="C0SP1:attr.3">multiplicatively-closed</a>  <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c1">R</font>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide">  for <font color="Olive" title="b1">a</font> being    <a href="subset_1.html#M2" title="SUBSET_1:mode.2">Element</a> of  <a href="ringfrac.html#K6" title="RINGFRAC:func.6">Frac</a> <font color="Maroon" title="c2">S</font>  st <font color="Olive" title="b1">a</font> <a href="domain_1.html#K2" title="DOMAIN_1:func.2">`1</a>  <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b1">a</font> <a href="domain_1.html#K3" title="DOMAIN_1:func.3">`2</a>  holds <br/> <a href="eqrel_1.html#K6" title="EQREL_1:func.6">Class</a> (<span class="p1">(<span class="default"><a href="ringfrac.html#K12" title="RINGFRAC:func.12">EqRel</a> <font color="Maroon" title="c2">S</font></span>)</span>,<font color="Olive" title="b1">a</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <span class="p1">(<span class="default"><font color="Maroon" title="c2">S</font> <a href="ringfrac.html#NK17" title="RINGFRAC:NK.17">~</a> <font color="Maroon" title="c1">R</font></span>)</span></span><br/><span class="kw">let </span><font color="Maroon" title="c3">a</font> be    <a href="subset_1.html#M2" title="SUBSET_1:mode.2">Element</a> of  <a href="ringfrac.html#K6" title="RINGFRAC:func.6">Frac</a> <font color="Maroon" title="c2">S</font>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( <font color="Maroon" title="c3">a</font> <a href="domain_1.html#K2" title="DOMAIN_1:func.2">`1</a>  <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">a</font> <a href="domain_1.html#K3" title="DOMAIN_1:func.3">`2</a>  implies  <a href="eqrel_1.html#K6" title="EQREL_1:func.6">Class</a> (<span class="p1">(<span class="default"><a href="ringfrac.html#K12" title="RINGFRAC:func.12">EqRel</a> <font color="Maroon" title="c2">S</font></span>)</span>,<font color="Maroon" title="c3">a</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <span class="p1">(<span class="default"><font color="Maroon" title="c2">S</font> <a href="ringfrac.html#NK17" title="RINGFRAC:NK.17">~</a> <font color="Maroon" title="c1">R</font></span>)</span> )</span><br/>





<span class="kw">assume </span><a NAME="E1:68"/><span class="lab"><font color="Green" title="E45">A1</font></span>: 
<font color="Maroon" title="c3">a</font> <a href="domain_1.html#K2" title="DOMAIN_1:func.2">`1</a>  <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">a</font> <a href="domain_1.html#K3" title="DOMAIN_1:func.3">`2</a> 
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide">  <a href="eqrel_1.html#K6" title="EQREL_1:func.6">Class</a> (<span class="p1">(<span class="default"><a href="ringfrac.html#K12" title="RINGFRAC:func.12">EqRel</a> <font color="Maroon" title="c2">S</font></span>)</span>,<font color="Maroon" title="c3">a</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <span class="p1">(<span class="default"><font color="Maroon" title="c2">S</font> <a href="ringfrac.html#NK17" title="RINGFRAC:NK.17">~</a> <font color="Maroon" title="c1">R</font></span>)</span></span><br/>

<span class="kw">reconsider </span><font color="Maroon" title="c4">s1</font> =  <a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <font color="Maroon" title="c1">R</font> as    <a href="subset_1.html#M2" title="SUBSET_1:mode.2">Element</a> of <font color="Maroon" title="c2">S</font> <span class="kw">by</span> <span class="lab"><a class="ref" href="c0sp1.html#D4" onmouseover="rs('c0sp1/D4')" onmouseout="rh()">C0SP1:def 4</a></span>;<br/>
<a NAME="E3:68"/>
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><font color="Maroon" title="c3">a</font> <a href="domain_1.html#K2" title="DOMAIN_1:func.2">`1</a></span>)</span> <a href="group_1.html#K8" title="GROUP_1:func.8">*</a> <span class="p3">(<span class="default"><span class="p4">(<span class="default"><a href="ringfrac.html#K14" title="RINGFRAC:func.14">1.</a> (<font color="Maroon" title="c1">R</font>,<font color="Maroon" title="c2">S</font>)</span>)</span> <a href="domain_1.html#K3" title="DOMAIN_1:func.3">`2</a></span>)</span></span>)</span> <a href="algstr_0.html#K5" title="ALGSTR_0:func.5">-</a> <span class="p2">(<span class="default"><span class="p3">(<span class="default"><span class="p4">(<span class="default"><a href="ringfrac.html#K14" title="RINGFRAC:func.14">1.</a> (<font color="Maroon" title="c1">R</font>,<font color="Maroon" title="c2">S</font>)</span>)</span> <a href="domain_1.html#K2" title="DOMAIN_1:func.2">`1</a></span>)</span> <a href="group_1.html#K8" title="GROUP_1:func.8">*</a> <span class="p3">(<span class="default"><font color="Maroon" title="c3">a</font> <a href="domain_1.html#K3" title="DOMAIN_1:func.3">`2</a></span>)</span></span>)</span></span>)</span> <a href="group_1.html#K8" title="GROUP_1:func.8">*</a> <font color="Maroon" title="c4">s1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="struct_0.html#K4" title="STRUCT_0:func.4">0.</a> <font color="Maroon" title="c1">R</font>
 
<span class="kw">by</span> <span class="lab"><a class="txt" href="#E1:68"><span class="lab"><font color="Green" title="E45">A1</font></span></a>, <a class="ref" href="rlvect_1.html#T5" onmouseover="rs('rlvect_1/T5')" onmouseout="rh()">RLVECT_1:5</a></span>;<br/>
<a NAME="E4:68"/><span class="kw">then </span>
<font color="Maroon" title="c3">a</font>, <a href="ringfrac.html#K14" title="RINGFRAC:func.14">1.</a> (<font color="Maroon" title="c1">R</font>,<font color="Maroon" title="c2">S</font>) <a href="ringfrac.html#R1" title="RINGFRAC:pred.1">Fr_Eq</a> <font color="Maroon" title="c2">S</font>
 
;<br/>
<span class="kw">then </span> <a href="eqrel_1.html#K6" title="EQREL_1:func.6">Class</a> (<span class="p1">(<span class="default"><a href="ringfrac.html#K12" title="RINGFRAC:func.12">EqRel</a> <font color="Maroon" title="c2">S</font></span>)</span>,<font color="Maroon" title="c3">a</font>) = 
 <a href="eqrel_1.html#K6" title="EQREL_1:func.6">Class</a> (<span class="p1">(<span class="default"><a href="ringfrac.html#K12" title="RINGFRAC:func.12">EqRel</a> <font color="Maroon" title="c2">S</font></span>)</span>,<span class="p1">(<span class="default"><a href="ringfrac.html#K14" title="RINGFRAC:func.14">1.</a> (<font color="Maroon" title="c1">R</font>,<font color="Maroon" title="c2">S</font>)</span>)</span>)
<span class="kw">by</span> <span class="lab"><a class="ref" href="ringfrac.html#T19" target="_self" onmouseover="rs('ringfrac/T19')" onmouseout="rh()">Th26</a></span>
<br/>.= 
 <a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <span class="p1">(<span class="default"><font color="Maroon" title="c2">S</font> <a href="ringfrac.html#NK17" title="RINGFRAC:NK.17">~</a> <font color="Maroon" title="c1">R</font></span>)</span>
<span class="kw">by</span> <span class="lab"><a class="ref" href="ringfrac.html#D18" target="_self" onmouseover="rs('ringfrac/D18')" onmouseout="rh()">Def6</a></span>
;<br/>
<span class="kw">hence </span><a NAME="E6:68"/>
 <a href="eqrel_1.html#K6" title="EQREL_1:func.6">Class</a> (<span class="p1">(<span class="default"><a href="ringfrac.html#K12" title="RINGFRAC:func.12">EqRel</a> <font color="Maroon" title="c2">S</font></span>)</span>,<font color="Maroon" title="c3">a</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <span class="p1">(<span class="default"><font color="Maroon" title="c2">S</font> <a href="ringfrac.html#NK17" title="RINGFRAC:NK.17">~</a> <font color="Maroon" title="c1">R</font></span>)</span>
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


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