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<b>let </b><font color="Maroon" title="c1">x1</font> be   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <a href="vectsp_1.html#K2" title="VECTSP_1:func.2">F_Real</a> ;<br/><b>let </b><font color="Maroon" title="c2">x2</font> be   <a href="real_1.html#NM1" title="REAL_1:NM.1">Real</a>;<br/>



<b>assume </b><a NAME="E1:17"/><i><font color="Green" title="E9">A1</font></i>: 
<font color="Maroon" title="c1">x1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c2">x2</font>
 ;<br/>

<b>reconsider </b><font color="Maroon" title="c3">x3</font> = <font color="Maroon" title="c1">x1</font> as    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of  <a href="numbers.html#K1" title="NUMBERS:func.1">REAL</a>  <b>by </b><i><a class="ref" href="vectsp_1.html#D15" title="VECTSP_1:def.15">VECTSP_1:def 15</a></i>;<br/>
<b>reconsider </b><font color="Maroon" title="c4">x'</font> =  <a href="real_1.html#K1" title="REAL_1:func.1">-</a> <font color="Maroon" title="c2">x2</font> as   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <a href="vectsp_1.html#K2" title="VECTSP_1:func.2">F_Real</a>  <b>by </b><i><a class="ref" href="vectsp_1.html#D15" title="VECTSP_1:def.15">VECTSP_1:def 15</a></i>;<br/>
<b>thus </b><a NAME="E4:17"/>
 <a href="rlvect_1.html#K4" title="RLVECT_1:func.4">-</a> <font color="Maroon" title="c1">x1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="real_1.html#K1" title="REAL_1:func.1">-</a> <font color="Maroon" title="c2">x2</font>
 <b>by </b><i><a class="txt" href="matrix10.html#E1:17"><i><font color="Green" title="E9">A1</font></i></a></i>;<br/>


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