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<b>let </b><font color="Maroon">FdSp</font> be   <a href="parsp_2.html#NM1">FanodesSp</a>;<br/><b>let </b><font color="Maroon">o</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">FdSp</font>;<br/><b>let </b><font color="Maroon">a</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">FdSp</font>;<br/><b>let </b><font color="Maroon">b</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">FdSp</font>;<br/><b>let </b><font color="Maroon">x</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">FdSp</font>;<br/>









<b>assume </b><a NAME="E1:32"/><i><font color="Green">E17</font></i>: 
not <font color="Maroon">o</font>,<font color="Maroon">a</font>,<font color="Maroon">b</font> <a href="parsp_2.html#R1" target="_self">is_collinear</a> 
 ;<br/>

<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="32_1"><b>now </b></a><div class="add"><b>assume </b><a NAME="E1:32_1"/>
( <font color="Maroon">o</font>,<font color="Maroon">a</font>,<font color="Maroon">x</font> <a href="parsp_2.html#R1" target="_self">is_collinear</a>  &amp; <font color="Maroon">o</font>,<font color="Maroon">b</font>,<font color="Maroon">x</font> <a href="parsp_2.html#R1" target="_self">is_collinear</a>  )
 ;<br/><a NAME="E2:32_1"/><b>then </b>
( not <font color="Maroon">a</font>,<font color="Maroon">b</font>,<font color="Maroon">o</font> <a href="parsp_2.html#R1" target="_self">is_collinear</a>  &amp; <font color="Maroon">a</font>,<font color="Maroon">o</font>,<font color="Maroon">x</font> <a href="parsp_2.html#R1" target="_self">is_collinear</a>  &amp; <font color="Maroon">o</font>,<font color="Maroon">b</font>,<font color="Maroon">x</font> <a href="parsp_2.html#R1" target="_self">is_collinear</a>  &amp; <font color="Maroon">b</font>,<font color="Maroon">o</font>,<font color="Maroon">x</font> <a href="parsp_2.html#R1" target="_self">is_collinear</a>  )
 <b>by </b><i>, </i>;<br/><a NAME="E3:32_1"/><b>then </b>
( not <font color="Maroon">a</font>,<font color="Maroon">b</font> <a href="parsp_1.html#R1">'||'</a> <font color="Maroon">a</font>,<font color="Maroon">o</font> &amp; <font color="Maroon">a</font>,<font color="Maroon">o</font> <a href="parsp_1.html#R1">'||'</a> <font color="Maroon">a</font>,<font color="Maroon">x</font> &amp; <font color="Maroon">b</font>,<font color="Maroon">o</font> <a href="parsp_1.html#R1">'||'</a> <font color="Maroon">b</font>,<font color="Maroon">x</font> )
 <b>by </b><i/>;<br/><b>hence </b><a NAME="E4:32_1"/>
(  not <font color="Maroon">o</font>,<font color="Maroon">a</font>,<font color="Maroon">x</font> <a href="parsp_2.html#R1" target="_self">is_collinear</a>  or  not <font color="Maroon">o</font>,<font color="Maroon">b</font>,<font color="Maroon">x</font> <a href="parsp_2.html#R1" target="_self">is_collinear</a>  or <font color="Maroon">o</font> <a href="hidden.html#R1">=</a> <font color="Maroon">x</font> )
 <b>by </b><i><a class="ref" href="parsp_1.html#T51">PARSP_1:51</a></i>;<br/></div><b>end;</b></div>
<b>hence </b><a NAME="E3:32"/>
(  not <font color="Maroon">o</font>,<font color="Maroon">a</font>,<font color="Maroon">x</font> <a href="parsp_2.html#R1" target="_self">is_collinear</a>  or  not <font color="Maroon">o</font>,<font color="Maroon">b</font>,<font color="Maroon">x</font> <a href="parsp_2.html#R1" target="_self">is_collinear</a>  or <font color="Maroon">o</font> <a href="hidden.html#R1">=</a> <font color="Maroon">x</font> )
 ;<br/>


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