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<b>set </b><font color="Maroon" title="c3">M</font> =  <a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font>;<br/>
<a NAME="E1:39_1_1"/>
the <a href="struct_0.html#U1" title="STRUCT_0:sel.1">carrier</a> of <span class="p1">(<span class="default"><a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> the <a href="struct_0.html#U1" title="STRUCT_0:sel.1">carrier</a> of <font color="Maroon" title="c2">V</font>
 
<b>by </b><i><a class="ref" href="matroid0.html#D9" target="_self" title="MATROID0:def.9">Def5</a></i>;<br/>
<b>hence </b><a NAME="E2:39_1_1"/>
not the <a href="struct_0.html#U1" title="STRUCT_0:sel.1">carrier</a> of <span class="p1">(<span class="default"><a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font></span>)</span> is <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>
 ; <i><font color="Red">:: according to </font></i><a class="ref" href="struct_0.html#D1" title="STRUCT_0:def.1">STRUCT_0:def 1</a> <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> ( not  <a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font> is <a href="pencil_1.html#V3" title="PENCIL_1:attr.3">void</a> &amp;  <a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font> is <a href="matroid0.html#V1" title="MATROID0:attr.1">subset-closed</a> )</span><br/>

<a NAME="E3:39_1_1"/><i><font color="Green" title="E16">A2</font></i>: 
 <a href="matroid0.html#K1" title="MATROID0:func.1">the_family_of</a> <span class="p1">(<span class="default"><a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1">{<span class="default"> <font color="Olive" title="b1">A</font> where <font color="Olive" title="b1">A</font> is   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c2">V</font> : <font color="Olive" title="b1">A</font> is <a href="vectsp_7.html#V1" title="VECTSP_7:attr.1">linearly-independent</a> </span>}</span> 
 
<b>by </b><i><a class="ref" href="matroid0.html#D9" target="_self" title="MATROID0:def.9">Def5</a></i>;<br/>
<a NAME="E4:39_1_1"/>
 <a href="struct_0.html#K1" title="STRUCT_0:func.1">{}</a> <font color="Maroon" title="c2">V</font> is <a href="vectsp_7.html#V1" title="VECTSP_7:attr.1">linearly-independent</a>
 
;<br/>
<a NAME="E5:39_1_1"/><b>then </b>
 <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="matroid0.html#K1" title="MATROID0:func.1">the_family_of</a> <span class="p1">(<span class="default"><a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font></span>)</span>
 
<b>by </b><i><a class="txt" href="#E3:39_1_1"><i><font color="Green" title="E16">A2</font></i></a></i>;<br/>
<b>hence </b><a NAME="E6:39_1_1"/>
not the <a href="pre_topc.html#U1" title="PRE_TOPC:sel.1">topology</a> of <span class="p1">(<span class="default"><a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font></span>)</span> is <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>
 ; <i><font color="Red">:: according to </font></i><a class="ref" href="pencil_1.html#D4" title="PENCIL_1:def.4">PENCIL_1:def 4</a> <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide">  <a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font> is <a href="matroid0.html#V1" title="MATROID0:attr.1">subset-closed</a></span><br/>

<b>let </b><font color="Maroon" title="c4">x</font>, <font color="Maroon" title="c5">y</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ; <i><font color="Red">:: according to </font></i><a class="ref" href="classes1.html#D1" title="CLASSES1:def.1">CLASSES1:def 1</a>,<a class="ref" href="matroid0.html#D3" target="_self" title="MATROID0:def.3">MATROID0:def 3</a> <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> (  not <font color="Maroon" title="c4">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="matroid0.html#K1" title="MATROID0:func.1">the_family_of</a> <span class="p1">(<span class="default"><a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font></span>)</span> or <font color="Maroon" title="c5">y</font> <a href="matroid0.html#NR1" title="MATROID0:NR.1">c/=</a> <font color="Maroon" title="c4">x</font> or <font color="Maroon" title="c5">y</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="matroid0.html#K1" title="MATROID0:func.1">the_family_of</a> <span class="p1">(<span class="default"><a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font></span>)</span> )</span><br/>

<b>assume </b><a NAME="E7:39_1_1"/>
<font color="Maroon" title="c4">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="matroid0.html#K1" title="MATROID0:func.1">the_family_of</a> <span class="p1">(<span class="default"><a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font></span>)</span>
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> ( <font color="Maroon" title="c5">y</font> <a href="matroid0.html#NR1" title="MATROID0:NR.1">c/=</a> <font color="Maroon" title="c4">x</font> or <font color="Maroon" title="c5">y</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="matroid0.html#K1" title="MATROID0:func.1">the_family_of</a> <span class="p1">(<span class="default"><a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font></span>)</span> )</span><br/>

<b>then consider </b><font color="Maroon" title="c6">A</font> being   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c2">V</font><b> such that </b><br/><a NAME="E9:39_1_1"/><i><font color="Green" title="E17">A3</font></i>: 
( <font color="Maroon" title="c4">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c6">A</font> &amp; <font color="Maroon" title="c6">A</font> is <a href="vectsp_7.html#V1" title="VECTSP_7:attr.1">linearly-independent</a> )
 <b>by </b><i><a class="txt" href="#E3:39_1_1"><i><font color="Green" title="E16">A2</font></i></a></i>;<br/>
<b>assume </b><a NAME="E10:39_1_1"/><i><font color="Green" title="E18">A4</font></i>: 
<font color="Maroon" title="c5">y</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a> <font color="Maroon" title="c4">x</font>
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> <font color="Maroon" title="c5">y</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="matroid0.html#K1" title="MATROID0:func.1">the_family_of</a> <span class="p1">(<span class="default"><a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font></span>)</span></span><br/>

<b>then reconsider </b><font color="Maroon" title="c7">B</font> = <font color="Maroon" title="c5">y</font> as   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c2">V</font> <b>by </b><i><a class="txt" href="#E9:39_1_1"><i><font color="Green" title="E17">A3</font></i></a>, <a class="ref" href="xboole_1.html#T1" title="XBOOLE_1:th.1">XBOOLE_1:1</a></i>;<br/>
<a NAME="E12:39_1_1"/>
<font color="Maroon" title="c7">B</font> is <a href="vectsp_7.html#V1" title="VECTSP_7:attr.1">linearly-independent</a>
 
<b>by </b><i><a class="txt" href="#E9:39_1_1"><i><font color="Green" title="E17">A3</font></i></a>, <a class="txt" href="#E10:39_1_1"><i><font color="Green" title="E18">A4</font></i></a>, <a class="ref" href="vectsp_7.html#T2" title="VECTSP_7:th.2">VECTSP_7:2</a></i>;<br/>
<b>hence </b><a NAME="E13:39_1_1"/>
<font color="Maroon" title="c5">y</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="matroid0.html#K1" title="MATROID0:func.1">the_family_of</a> <span class="p1">(<span class="default"><a href="matroid0.html#K3" title="MATROID0:func.3">LinearlyIndependentSubsets</a> <font color="Maroon" title="c2">V</font></span>)</span>
 <b>by </b><i><a class="txt" href="#E3:39_1_1"><i><font color="Green" title="E16">A2</font></i></a></i>; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> verum</span><br/>


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