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<span class="kw">let </span><font color="Maroon" title="c1">I</font> be  non  <a href="struct_0.html#V6" title="STRUCT_0:attr.6">degenerated</a>   <a href="group_1.html#V5" title="GROUP_1:attr.5">commutative</a>   <a href="vectsp_2.html#V1" title="VECTSP_2:attr.1">domRing-like</a>  <a href="funcsdom.html#NM1" title="FUNCSDOM:NM.1">Ring</a>; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="Red">::  thesis: </font></span></a><span class="hide">  <a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font> is  <a href="quofield.html#V3" title="QUOFIELD:attr.3">RingMonomorphism</a> </span><br/>

<a NAME="E1:95"/><span class="lab"><font color="Green" title="E69">A1</font></span>: 
 <a href="struct_0.html#K4" title="STRUCT_0:func.4">0.</a> <font color="Maroon" title="c1">I</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a>  <a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <font color="Maroon" title="c1">I</font>
 
;<br/>
<a NAME="E2:95"/>
for <font color="Olive" title="b1">x1</font>, <font color="Olive" title="b2">x2</font> being   <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a>   st <font color="Olive" title="b1">x1</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="relset_1.html#K1" title="RELSET_1:func.1">dom</a> <span class="p1">(<span class="default"><a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font></span>)</span> &amp; <font color="Olive" title="b2">x2</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="relset_1.html#K1" title="RELSET_1:func.1">dom</a> <span class="p1">(<span class="default"><a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font></span>)</span> &amp; <span class="p1">(<span class="default"><a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font></span>)</span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">x1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1">(<span class="default"><a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font></span>)</span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b2">x2</font> holds <br/><font color="Olive" title="b1">x1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b2">x2</font>
 
<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="95_1"><span class="kw">proof </span></a><div class="add">

<span class="kw">let </span><font color="Maroon" title="c2">x1</font>, <font color="Maroon" title="c3">x2</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="Red">::  thesis: </font></span></a><span class="hide"> ( <font color="Maroon" title="c2">x1</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="relset_1.html#K1" title="RELSET_1:func.1">dom</a> <span class="p1">(<span class="default"><a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font></span>)</span> &amp; <font color="Maroon" title="c3">x2</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="relset_1.html#K1" title="RELSET_1:func.1">dom</a> <span class="p1">(<span class="default"><a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font></span>)</span> &amp; <span class="p1">(<span class="default"><a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font></span>)</span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c2">x1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1">(<span class="default"><a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font></span>)</span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c3">x2</font> implies <font color="Maroon" title="c2">x1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">x2</font> )</span><br/>

<span class="kw">assume </span><span class="kw">that </span><br/><a NAME="E1:95_1"/><span class="lab"><font color="Green" title="E70">A2</font></span>: 
( <font color="Maroon" title="c2">x1</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="relset_1.html#K1" title="RELSET_1:func.1">dom</a> <span class="p1">(<span class="default"><a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font></span>)</span> &amp; <font color="Maroon" title="c3">x2</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="relset_1.html#K1" title="RELSET_1:func.1">dom</a> <span class="p1">(<span class="default"><a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font></span>)</span> )
 <span class="kw">and </span><br/><a NAME="E2:95_1"/><span class="lab"><font color="Green" title="E71">A3</font></span>: 
<span class="p1">(<span class="default"><a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font></span>)</span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c2">x1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1">(<span class="default"><a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font></span>)</span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c3">x2</font>
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="Red">::  thesis: </font></span></a><span class="hide"> <font color="Maroon" title="c2">x1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">x2</font></span><br/>

<span class="kw">reconsider </span><font color="Maroon" title="c4">x1</font> = <font color="Maroon" title="c2">x1</font>, <font color="Maroon" title="c5">x2</font> = <font color="Maroon" title="c3">x2</font> as   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">I</font> <span class="kw">by</span> <span class="lab"><a class="txt" href="#E1:95_1"><span class="lab"><font color="Green" title="E70">A2</font></span></a></span>;<br/>
<span class="kw">reconsider </span><font color="Maroon" title="c6">t1</font> =  <a href="quofield.html#K23" title="QUOFIELD:func.23">quotient</a> <font color="Maroon" title="c4">x1</font>,<span class="p1">(<span class="default"><a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <font color="Maroon" title="c1">I</font></span>)</span>, <font color="Maroon" title="c7">t2</font> =  <a href="quofield.html#K23" title="QUOFIELD:func.23">quotient</a> <font color="Maroon" title="c5">x2</font>,<span class="p1">(<span class="default"><a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <font color="Maroon" title="c1">I</font></span>)</span> as    <a href="subset_1.html#M2" title="SUBSET_1:mode.2">Element</a> of  <a href="quofield.html#K1" title="QUOFIELD:func.1">Q.</a> <font color="Maroon" title="c1">I</font> ;<br/>
<a NAME="E5:95_1"/><span class="lab"><font color="Green" title="E72">A4</font></span>: 
<font color="Maroon" title="c6">t1</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="quofield.html#K12" title="QUOFIELD:func.12">QClass.</a> <font color="Maroon" title="c6">t1</font>
 
<span class="kw">by</span> <span class="lab"><a class="ref" href="quofield.html#T6" target="_self" title="QUOFIELD:th.6">Th6</a></span>;<br/>
 <a href="quofield.html#K12" title="QUOFIELD:func.12">QClass.</a> <font color="Maroon" title="c6">t1</font> = 
<span class="p1">(<span class="default"><a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font></span>)</span> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c5">x2</font>
<span class="kw">by</span> <span class="lab"><a class="txt" href="#E2:95_1"><span class="lab"><font color="Green" title="E71">A3</font></span></a>, <a class="ref" href="quofield.html#D28" target="_self" title="QUOFIELD:def.28">Def28</a></span>
<br/>.= 
 <a href="quofield.html#K12" title="QUOFIELD:func.12">QClass.</a> <font color="Maroon" title="c7">t2</font>
<span class="kw">by</span> <span class="lab"><a class="ref" href="quofield.html#D28" target="_self" title="QUOFIELD:def.28">Def28</a></span>
;<br/>
<a NAME="E7:95_1"/><span class="kw">then </span><span class="lab"><font color="Green" title="E73">A5</font></span>: 
<span class="p1">(<span class="default"><font color="Maroon" title="c6">t1</font> <a href="quofield.html#K2" title="QUOFIELD:func.2">`1</a> </span>)</span> <a href="group_1.html#K8" title="GROUP_1:func.8">*</a> <span class="p1">(<span class="default"><font color="Maroon" title="c7">t2</font> <a href="quofield.html#K3" title="QUOFIELD:func.3">`2</a> </span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1">(<span class="default"><font color="Maroon" title="c6">t1</font> <a href="quofield.html#K3" title="QUOFIELD:func.3">`2</a> </span>)</span> <a href="group_1.html#K8" title="GROUP_1:func.8">*</a> <span class="p1">(<span class="default"><font color="Maroon" title="c7">t2</font> <a href="quofield.html#K2" title="QUOFIELD:func.2">`1</a> </span>)</span>
 
<span class="kw">by</span> <span class="lab"><a class="txt" href="#E5:95_1"><span class="lab"><font color="Green" title="E72">A4</font></span></a>, <a class="ref" href="quofield.html#D4" target="_self" title="QUOFIELD:def.4">Def4</a></span>;<br/>
<span class="lab"><font color="Green" title="E74">A6</font></span>: <font color="Maroon" title="c6">t1</font> <a href="quofield.html#K3" title="QUOFIELD:func.3">`2</a>  = 
<span class="p1"><a href="domain_1.html#K1" title="DOMAIN_1:func.1">[</a><span class="default"><font color="Maroon" title="c4">x1</font>,<span class="p2">(<span class="default"><a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <font color="Maroon" title="c1">I</font></span>)</span></span><a href="domain_1.html#K1" title="DOMAIN_1:func.1">]</a></span> <a href="domain_1.html#K3" title="DOMAIN_1:func.3">`2</a> 
<span class="kw">by</span> <span class="lab"><a class="txt" href="#E1:95"><span class="lab"><font color="Green" title="E69">A1</font></span></a>, <a class="ref" href="quofield.html#D27" target="_self" title="QUOFIELD:def.27">Def27</a></span>
<br/>.= 
 <a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <font color="Maroon" title="c1">I</font>
<span class="kw">by</span> <span class="lab"><a class="ref" href="mcart_1.html#D2" title="MCART_1:def.2">MCART_1:def 2</a></span>
;<br/>
<span class="lab"><font color="Green" title="E75">A7</font></span>: <font color="Maroon" title="c6">t1</font> <a href="quofield.html#K2" title="QUOFIELD:func.2">`1</a>  = 
<span class="p1"><a href="domain_1.html#K1" title="DOMAIN_1:func.1">[</a><span class="default"><font color="Maroon" title="c4">x1</font>,<span class="p2">(<span class="default"><a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <font color="Maroon" title="c1">I</font></span>)</span></span><a href="domain_1.html#K1" title="DOMAIN_1:func.1">]</a></span> <a href="domain_1.html#K2" title="DOMAIN_1:func.2">`1</a> 
<span class="kw">by</span> <span class="lab"><a class="txt" href="#E1:95"><span class="lab"><font color="Green" title="E69">A1</font></span></a>, <a class="ref" href="quofield.html#D27" target="_self" title="QUOFIELD:def.27">Def27</a></span>
<br/>.= 
<font color="Maroon" title="c4">x1</font>
<span class="kw">by</span> <span class="lab"><a class="ref" href="mcart_1.html#D1" title="MCART_1:def.1">MCART_1:def 1</a></span>
;<br/>
<span class="lab"><font color="Green" title="E76">A8</font></span>: <font color="Maroon" title="c7">t2</font> <a href="quofield.html#K2" title="QUOFIELD:func.2">`1</a>  = 
<span class="p1"><a href="domain_1.html#K1" title="DOMAIN_1:func.1">[</a><span class="default"><font color="Maroon" title="c5">x2</font>,<span class="p2">(<span class="default"><a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <font color="Maroon" title="c1">I</font></span>)</span></span><a href="domain_1.html#K1" title="DOMAIN_1:func.1">]</a></span> <a href="domain_1.html#K2" title="DOMAIN_1:func.2">`1</a> 
<span class="kw">by</span> <span class="lab"><a class="txt" href="#E1:95"><span class="lab"><font color="Green" title="E69">A1</font></span></a>, <a class="ref" href="quofield.html#D27" target="_self" title="QUOFIELD:def.27">Def27</a></span>
<br/>.= 
<font color="Maroon" title="c5">x2</font>
<span class="kw">by</span> <span class="lab"><a class="ref" href="mcart_1.html#D1" title="MCART_1:def.1">MCART_1:def 1</a></span>
;<br/>
<font color="Maroon" title="c7">t2</font> <a href="quofield.html#K3" title="QUOFIELD:func.3">`2</a>  = 
<span class="p1"><a href="domain_1.html#K1" title="DOMAIN_1:func.1">[</a><span class="default"><font color="Maroon" title="c5">x2</font>,<span class="p2">(<span class="default"><a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <font color="Maroon" title="c1">I</font></span>)</span></span><a href="domain_1.html#K1" title="DOMAIN_1:func.1">]</a></span> <a href="domain_1.html#K3" title="DOMAIN_1:func.3">`2</a> 
<span class="kw">by</span> <span class="lab"><a class="txt" href="#E1:95"><span class="lab"><font color="Green" title="E69">A1</font></span></a>, <a class="ref" href="quofield.html#D27" target="_self" title="QUOFIELD:def.27">Def27</a></span>
<br/>.= 
 <a href="struct_0.html#K5" title="STRUCT_0:func.5">1.</a> <font color="Maroon" title="c1">I</font>
<span class="kw">by</span> <span class="lab"><a class="ref" href="mcart_1.html#D2" title="MCART_1:def.2">MCART_1:def 2</a></span>
;<br/>
<span class="kw">then </span><font color="Maroon" title="c4">x1</font> = 
<span class="p1">(<span class="default"><font color="Maroon" title="c6">t1</font> <a href="quofield.html#K3" title="QUOFIELD:func.3">`2</a> </span>)</span> <a href="group_1.html#K8" title="GROUP_1:func.8">*</a> <span class="p1">(<span class="default"><font color="Maroon" title="c7">t2</font> <a href="quofield.html#K2" title="QUOFIELD:func.2">`1</a> </span>)</span>
<span class="kw">by</span> <span class="lab"><a class="txt" href="#E7:95_1"><span class="lab"><font color="Green" title="E73">A5</font></span></a>, <a class="txt" href="#E9:95_1"><span class="lab"><font color="Green" title="E75">A7</font></span></a>, <a class="ref" href="vectsp_1.html#D16" title="VECTSP_1:def.16">VECTSP_1:def 16</a></span>
<br/>.= 
<font color="Maroon" title="c5">x2</font>
<span class="kw">by</span> <span class="lab"><a class="txt" href="#E8:95_1"><span class="lab"><font color="Green" title="E74">A6</font></span></a>, <a class="txt" href="#E10:95_1"><span class="lab"><font color="Green" title="E76">A8</font></span></a>, <a class="ref" href="vectsp_1.html#D16" title="VECTSP_1:def.16">VECTSP_1:def 16</a></span>
;<br/>
<span class="kw">hence </span><a NAME="E13:95_1"/>
<font color="Maroon" title="c2">x1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">x2</font>
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="Red">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


</div><span class="kw">end;</span></div>
<a NAME="E3:95"/><span class="kw">then </span><span class="lab"><font color="Green" title="E70">A9</font></span>: 
 <a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font> is  <a href="funct_1.html#V2" title="FUNCT_1:attr.2">one-to-one</a> 
 
<span class="kw">by</span> <span class="lab"><a class="ref" href="funct_1.html#D8" title="FUNCT_1:def.8">FUNCT_1:def 8</a></span>;<br/>
<a NAME="E4:95"/>
 <a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font> is  <a href="quofield.html#V1" title="QUOFIELD:attr.1">RingHomomorphism</a> 
 
<span class="kw">by</span> <span class="lab"><a class="ref" href="quofield.html#T59" target="_self" title="QUOFIELD:th.59">Th59</a></span>;<br/>
<span class="kw">hence </span><a NAME="E5:95"/>
 <a href="quofield.html#K24" title="QUOFIELD:func.24">canHom</a> <font color="Maroon" title="c1">I</font> is  <a href="quofield.html#V3" title="QUOFIELD:attr.3">RingMonomorphism</a> 
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E3:95"><span class="lab"><font color="Green" title="E70">A9</font></span></a>, <a class="ref" href="quofield.html#D23" target="_self" title="QUOFIELD:def.23">Def23</a></span>; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="Red">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


</div>
