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<b>let </b><font color="Maroon">V</font> be   <a href="rlvect_1.html#NM2">RealLinearSpace</a>;<br/><b>let </b><font color="Maroon">x</font> be   <a href="rlvect_1.html#NM1">VECTOR</a> of <font color="Maroon">V</font>;<br/><b>let </b><font color="Maroon">y</font> be   <a href="rlvect_1.html#NM1">VECTOR</a> of <font color="Maroon">V</font>;<br/><b>let </b><font color="Maroon">u</font> be   <a href="rlvect_1.html#NM1">VECTOR</a> of <font color="Maroon">V</font>;<br/><b>let </b><font color="Maroon">v</font> be   <a href="rlvect_1.html#NM1">VECTOR</a> of <font color="Maroon">V</font>;<br/><b>let </b><font color="Maroon">u1</font> be   <a href="rlvect_1.html#NM1">VECTOR</a> of <font color="Maroon">V</font>;<br/><b>let </b><font color="Maroon">v1</font> be   <a href="rlvect_1.html#NM1">VECTOR</a> of <font color="Maroon">V</font>;<br/>













<b>assume </b><a NAME="E1:40"/><i><font color="Green">E39</font></i>: 
 <a href="analmetr.html#R1">Gen</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>
 ;<br/>

<div><i><font color="Green">E40</font></i>: <a class="txt" onclick="hs2(this)" href="javascript:()" title="40_1"><b>now </b></a><div class="add"><b>assume </b><a NAME="E1:40_1"/>
<font color="Maroon">u</font> <a href="hidden.html#R1">=</a> <font color="Maroon">v</font>
 ;<br/><a NAME="E2:40_1"/><b>then </b>
<font color="Maroon">v</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u</font> <a href="hidden.html#R1">=</a>  <a href="rlvect_1.html#K1">0.</a> <font color="Maroon">V</font>
 <b>by </b><i><a class="ref" href="rlvect_1.html#T28">RLVECT_1:28</a></i>;<br/><a NAME="E3:40_1"/><b>then </b>
<font color="Maroon">v</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u</font>,<font color="Maroon">v1</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u1</font> <a href="analmetr.html#R2">are_Ort_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>
 <b>by </b><i>, <a class="ref" href="analmetr.html#T9">ANALMETR:9</a></i>;<br/><b>hence </b><a NAME="E4:40_1"/>
<font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">u1</font>,<font color="Maroon">v1</font> <a href="analmetr.html#R3">are_Ort_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>
 <b>by </b><i><a class="ref" href="analmetr.html#D3">ANALMETR:def 3</a></i>;<br/></div><b>end;</b></div>
<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="40_2"><b>now </b></a><div class="add"><b>assume </b><a NAME="E1:40_2"/><i><font color="Green">E44</font></i>: 
<font color="Maroon">u</font> <a href="hidden.html#NR2" target="_self">&lt;&gt;</a> <font color="Maroon">v</font>
 ;<br/><b>set </b><font color="Maroon">u2</font> =  <a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font>;<br/><b>set </b><font color="Maroon">v2</font> =  <a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font>;<br/><a NAME="E2:40_2"/><i><font color="Green">E45</font></i>: 
<font color="Maroon">v</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u</font> <a href="hidden.html#NR2" target="_self">&lt;&gt;</a>  <a href="rlvect_1.html#K1">0.</a> <font color="Maroon">V</font>
 <b>by </b><i>, <a class="ref" href="rlvect_1.html#T35">RLVECT_1:35</a></i>;<br/><a NAME="E3:40_2"/>
<font color="Maroon">u</font>,<font color="Maroon">v</font>, <a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font>, <a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font> <a href="analmetr.html#R3">are_Ort_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>
 <b>by </b><i>, </i>;<br/><a NAME="E4:40_2"/><b>then </b><i><font color="Green">E46</font></i>: 
<font color="Maroon">v</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u</font>,<span class="p1">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font></span>)</span> <a href="rlvect_1.html#K6">-</a> <span class="p1">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font></span>)</span> <a href="analmetr.html#R2">are_Ort_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>
 <b>by </b><i><a class="ref" href="analmetr.html#D3">ANALMETR:def 3</a></i>;<br/><div><i><font color="Green">E47</font></i>: <a class="txt" onclick="hs2(this)" href="javascript:()" title="40_2_1"><b>now </b></a><div class="add"><b>assume </b><a NAME="E1:40_2_1"/>
<font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">u1</font>,<font color="Maroon">v1</font> <a href="analmetr.html#R3">are_Ort_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>
 ;<br/><a NAME="E2:40_2_1"/><b>then </b>
<font color="Maroon">v</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u</font>,<font color="Maroon">v1</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u1</font> <a href="analmetr.html#R2">are_Ort_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>
 <b>by </b><i><a class="ref" href="analmetr.html#D3">ANALMETR:def 3</a></i>;<br/><a NAME="E3:40_2_1"/><b>then </b>
 ex <font color="Olive">a</font>, <font color="Olive">b</font> being  <a href="real_1.html#NM1">Real</a> st <br/>( <font color="Olive">a</font> <a href="rlvect_1.html#K3">*</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font></span>)</span> <a href="rlvect_1.html#K6">-</a> <span class="p2">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font></span>)</span></span>)</span> <a href="hidden.html#R1">=</a> <font color="Olive">b</font> <a href="rlvect_1.html#K3">*</a> <span class="p1">(<span class="default"><font color="Maroon">v1</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u1</font></span>)</span> &amp; ( <font color="Olive">a</font> <a href="hidden.html#NR2" target="_self">&lt;&gt;</a> 0 or <font color="Olive">b</font> <a href="hidden.html#NR2" target="_self">&lt;&gt;</a> 0 ) )
 <b>by </b><i>, , , <a class="ref" href="analmetr.html#T13">ANALMETR:13</a></i>;<br/><a NAME="E4:40_2_1"/><b>then </b>
(  <a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font>, <a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font> <a href="analoaf.html#R1">//</a> <font color="Maroon">u1</font>,<font color="Maroon">v1</font> or  <a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font>, <a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font> <a href="analoaf.html#R1">//</a> <font color="Maroon">v1</font>,<font color="Maroon">u1</font> )
 <b>by </b><i><a class="ref" href="analmetr.html#T18">ANALMETR:18</a></i>;<br/><b>hence </b><a NAME="E5:40_2_1"/>
( <font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">u1</font>,<font color="Maroon">v1</font> <a href="analort.html#R1" target="_self">are_COrte_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font> or <font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">v1</font>,<font color="Maroon">u1</font> <a href="analort.html#R1" target="_self">are_COrte_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font> )
 <b>by </b><i/>;<br/></div><b>end;</b></div><div><a class="txt" onclick="hs2(this)" href="javascript:()" title="40_2_2"><b>now </b></a><div class="add"><b>assume </b><a NAME="E1:40_2_2"/>
( <font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">u1</font>,<font color="Maroon">v1</font> <a href="analort.html#R1" target="_self">are_COrte_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font> or <font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">v1</font>,<font color="Maroon">u1</font> <a href="analort.html#R1" target="_self">are_COrte_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font> )
 ;<br/><a NAME="E2:40_2_2"/><b>then </b>
(  <a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font>, <a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font> <a href="analoaf.html#R1">//</a> <font color="Maroon">u1</font>,<font color="Maroon">v1</font> or  <a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font>, <a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font> <a href="analoaf.html#R1">//</a> <font color="Maroon">v1</font>,<font color="Maroon">u1</font> )
 <b>by </b><i/>;<br/><b>then consider </b><font color="Maroon">a</font> being   <a href="real_1.html#NM1">Real</a>, <font color="Maroon">b</font> being   <a href="real_1.html#NM1">Real</a><b> such that </b><br/><a NAME="E4:40_2_2"/><i><font color="Green">E48</font></i>: 
<font color="Maroon">a</font> <a href="rlvect_1.html#K3">*</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font></span>)</span> <a href="rlvect_1.html#K6">-</a> <span class="p2">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font></span>)</span></span>)</span> <a href="hidden.html#R1">=</a> <font color="Maroon">b</font> <a href="rlvect_1.html#K3">*</a> <span class="p1">(<span class="default"><font color="Maroon">v1</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u1</font></span>)</span>
 <b>and </b><br/><a NAME="E5:40_2_2"/><i><font color="Green">E49</font></i>: 
( <font color="Maroon">a</font> <a href="hidden.html#NR2" target="_self">&lt;&gt;</a> 0 or <font color="Maroon">b</font> <a href="hidden.html#NR2" target="_self">&lt;&gt;</a> 0 )
 <b>by </b><i><a class="ref" href="analmetr.html#T18">ANALMETR:18</a></i>;<br/><div><i><font color="Green">E79</font></i>: <a class="txt" onclick="hs2(this)" href="javascript:()" title="40_2_2_1"><b>now </b></a><div class="add"><b>assume </b><a NAME="E1:40_2_2_1"/><i><font color="Green">E80</font></i>: 
<font color="Maroon">b</font> <a href="hidden.html#R1">=</a> 0
 ;<br/><a NAME="E2:40_2_2_1"/><b>then </b>
 <a href="rlvect_1.html#K1">0.</a> <font color="Maroon">V</font> <a href="hidden.html#R1">=</a> <font color="Maroon">a</font> <a href="rlvect_1.html#K3">*</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font></span>)</span> <a href="rlvect_1.html#K6">-</a> <span class="p2">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font></span>)</span></span>)</span>
 <b>by </b><i>, <a class="ref" href="rlvect_1.html#T23">RLVECT_1:23</a></i>;<br/><a NAME="E3:40_2_2_1"/><b>then </b>
<span class="p1">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font></span>)</span> <a href="rlvect_1.html#K6">-</a> <span class="p1">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font></span>)</span> <a href="hidden.html#R1">=</a>  <a href="rlvect_1.html#K1">0.</a> <font color="Maroon">V</font>
 <b>by </b><i>, <a class="txt" href="analort.html#E1:40"><i><font color="Green">E39</font></i></a>, <a class="ref" href="rlvect_1.html#T24">RLVECT_1:24</a></i>;<br/><a NAME="E4:40_2_2_1"/><b>then </b>
 <a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font> <a href="hidden.html#R1">=</a>  <a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font>
 <b>by </b><i><a class="ref" href="rlvect_1.html#T35">RLVECT_1:35</a></i>;<br/><a NAME="E5:40_2_2_1"/><b>then </b>
<font color="Maroon">u</font> <a href="hidden.html#R1">=</a> <font color="Maroon">v</font>
 <b>by </b><i>, </i>;<br/><a NAME="E6:40_2_2_1"/><b>then </b>
<font color="Maroon">v</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u</font> <a href="hidden.html#R1">=</a>  <a href="rlvect_1.html#K1">0.</a> <font color="Maroon">V</font>
 <b>by </b><i><a class="ref" href="rlvect_1.html#T28">RLVECT_1:28</a></i>;<br/><a NAME="E7:40_2_2_1"/><b>then </b>
<font color="Maroon">v</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u</font>,<font color="Maroon">v1</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u1</font> <a href="analmetr.html#R2">are_Ort_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>
 <b>by </b><i>, <a class="ref" href="analmetr.html#T9">ANALMETR:9</a></i>;<br/><b>hence </b><a NAME="E8:40_2_2_1"/>
<font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">u1</font>,<font color="Maroon">v1</font> <a href="analmetr.html#R3">are_Ort_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>
 <b>by </b><i><a class="ref" href="analmetr.html#D3">ANALMETR:def 3</a></i>;<br/></div><b>end;</b></div><div><a class="txt" onclick="hs2(this)" href="javascript:()" title="40_2_2_2"><b>now </b></a><div class="add"><b>assume </b><a NAME="E1:40_2_2_2"/><i><font color="Green">E81</font></i>: 
<font color="Maroon">b</font> <a href="hidden.html#NR2" target="_self">&lt;&gt;</a> 0
 ;<br/><a NAME="E2:40_2_2_2"/>
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">b</font> <a href="real_1.html#K2">"</a> </span>)</span> <a href="real_1.html#K4">*</a> <font color="Maroon">a</font></span>)</span> <a href="rlvect_1.html#K3">*</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font></span>)</span> <a href="rlvect_1.html#K6">-</a> <span class="p2">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font></span>)</span></span>)</span> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><font color="Maroon">b</font> <a href="real_1.html#K2">"</a> </span>)</span> <a href="rlvect_1.html#K3">*</a> <span class="p1">(<span class="default"><font color="Maroon">b</font> <a href="rlvect_1.html#K3">*</a> <span class="p2">(<span class="default"><font color="Maroon">v1</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u1</font></span>)</span></span>)</span>
 <b>by </b><i>, <a class="ref" href="rlvect_1.html#D9">RLVECT_1:def 9</a></i>;<br/><a NAME="E3:40_2_2_2"/><b>then </b>
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">b</font> <a href="real_1.html#K2">"</a> </span>)</span> <a href="real_1.html#K4">*</a> <font color="Maroon">a</font></span>)</span> <a href="rlvect_1.html#K3">*</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font></span>)</span> <a href="rlvect_1.html#K6">-</a> <span class="p2">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font></span>)</span></span>)</span> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">b</font> <a href="real_1.html#K2">"</a> </span>)</span> <a href="real_1.html#K4">*</a> <font color="Maroon">b</font></span>)</span> <a href="rlvect_1.html#K3">*</a> <span class="p1">(<span class="default"><font color="Maroon">v1</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u1</font></span>)</span>
 <b>by </b><i><a class="ref" href="rlvect_1.html#D9">RLVECT_1:def 9</a></i>;<br/><a NAME="E4:40_2_2_2"/><b>then </b>
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">b</font> <a href="real_1.html#K2">"</a> </span>)</span> <a href="real_1.html#K4">*</a> <font color="Maroon">a</font></span>)</span> <a href="rlvect_1.html#K3">*</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font></span>)</span> <a href="rlvect_1.html#K6">-</a> <span class="p2">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font></span>)</span></span>)</span> <a href="hidden.html#R1">=</a> 1 <a href="rlvect_1.html#K3">*</a> <span class="p1">(<span class="default"><font color="Maroon">v1</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u1</font></span>)</span>
 <b>by </b><i><a class="txt" href="analort.html#E1:40"><i><font color="Green">E39</font></i></a>, <a class="ref" href="xcmplx_0.html#D7">XCMPLX_0:def 7</a></i>;<br/><a NAME="E5:40_2_2_2"/><b>then </b>
<font color="Maroon">v1</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u1</font> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon">b</font> <a href="real_1.html#K2">"</a> </span>)</span> <a href="real_1.html#K4">*</a> <font color="Maroon">a</font></span>)</span> <a href="rlvect_1.html#K3">*</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">v</font></span>)</span> <a href="rlvect_1.html#K6">-</a> <span class="p2">(<span class="default"><a href="analort.html#K3" target="_self">Orte</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>,<font color="Maroon">u</font></span>)</span></span>)</span>
 <b>by </b><i><a class="ref" href="rlvect_1.html#D9">RLVECT_1:def 9</a></i>;<br/><a NAME="E6:40_2_2_2"/><b>then </b>
<font color="Maroon">v</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u</font>,<font color="Maroon">v1</font> <a href="rlvect_1.html#K6">-</a> <font color="Maroon">u1</font> <a href="analmetr.html#R2">are_Ort_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>
 <b>by </b><i>, <a class="ref" href="analmetr.html#T11">ANALMETR:11</a></i>;<br/><b>hence </b><a NAME="E7:40_2_2_2"/>
<font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">u1</font>,<font color="Maroon">v1</font> <a href="analmetr.html#R3">are_Ort_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>
 <b>by </b><i><a class="ref" href="analmetr.html#D3">ANALMETR:def 3</a></i>;<br/></div><b>end;</b></div><b>hence </b><a NAME="E8:40_2_2"/>
<font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">u1</font>,<font color="Maroon">v1</font> <a href="analmetr.html#R3">are_Ort_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font>
 <b>by </b><i><a class="txt" href="analort.html#E1"><i><font color="Green">Lemma38</font></i></a></i>;<br/></div><b>end;</b></div><b>hence </b><a NAME="E7:40_2"/>
( <font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">u1</font>,<font color="Maroon">v1</font> <a href="analmetr.html#R3">are_Ort_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font> iff ( <font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">u1</font>,<font color="Maroon">v1</font> <a href="analort.html#R1" target="_self">are_COrte_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font> or <font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">v1</font>,<font color="Maroon">u1</font> <a href="analort.html#R1" target="_self">are_COrte_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font> ) )
 <b>by </b><i/>;<br/></div><b>end;</b></div>
<b>hence </b><a NAME="E4:40"/>
( <font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">u1</font>,<font color="Maroon">v1</font> <a href="analmetr.html#R3">are_Ort_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font> iff ( <font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">u1</font>,<font color="Maroon">v1</font> <a href="analort.html#R1" target="_self">are_COrte_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font> or <font color="Maroon">u</font>,<font color="Maroon">v</font>,<font color="Maroon">v1</font>,<font color="Maroon">u1</font> <a href="analort.html#R1" target="_self">are_COrte_wrt</a> <font color="Maroon">x</font>,<font color="Maroon">y</font> ) )
 <b>by </b><i>, </i>;<br/>


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