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<div><span class="kw">theorem </span><a NAME="T21"><span class="comment"><font color="firebrick">:: PAPPUS:21</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">o</font>, <font color="Olive" title="b2">p1</font>, <font color="Olive" title="b3">p2</font>, <font color="Olive" title="b4">p3</font>, <font color="Olive" title="b5">q1</font>, <font color="Olive" title="b6">q2</font>, <font color="Olive" title="b7">q3</font>, <font color="Olive" title="b8">r1</font>, <font color="Olive" title="b9">r2</font>, <font color="Olive" title="b10">r3</font> being   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <span class="p1">(<span class="default"><a href="anproj_1.html#K5" title="ANPROJ_1:func.5">ProjectiveSpace</a> <span class="p2">(<span class="default"><a href="euclid.html#K15" title="EUCLID:func.15">TOP-REAL</a> 3</span>)</span></span>)</span>  st <font color="Olive" title="b1">o</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a> <font color="Olive" title="b3">p2</font> &amp; <font color="Olive" title="b1">o</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a> <font color="Olive" title="b4">p3</font> &amp; <font color="Olive" title="b3">p2</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a> <font color="Olive" title="b4">p3</font> &amp; <font color="Olive" title="b2">p1</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a> <font color="Olive" title="b3">p2</font> &amp; <font color="Olive" title="b2">p1</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a> <font color="Olive" title="b4">p3</font> &amp; <font color="Olive" title="b1">o</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a> <font color="Olive" title="b6">q2</font> &amp; <font color="Olive" title="b1">o</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a> <font color="Olive" title="b7">q3</font> &amp; <font color="Olive" title="b6">q2</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a> <font color="Olive" title="b7">q3</font> &amp; <font color="Olive" title="b5">q1</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a> <font color="Olive" title="b6">q2</font> &amp; <font color="Olive" title="b5">q1</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a> <font color="Olive" title="b7">q3</font> &amp;  not <font color="Olive" title="b1">o</font>,<font color="Olive" title="b2">p1</font>,<font color="Olive" title="b5">q1</font> <a href="collsp.html#R1" title="COLLSP:pred.1">are_collinear</a>  &amp; <font color="Olive" title="b1">o</font>,<font color="Olive" title="b2">p1</font>,<font color="Olive" title="b3">p2</font> <a href="collsp.html#R1" title="COLLSP:pred.1">are_collinear</a>  &amp; <font color="Olive" title="b1">o</font>,<font color="Olive" title="b2">p1</font>,<font color="Olive" title="b4">p3</font> <a href="collsp.html#R1" title="COLLSP:pred.1">are_collinear</a>  &amp; <font color="Olive" title="b1">o</font>,<font color="Olive" title="b5">q1</font>,<font color="Olive" title="b6">q2</font> <a href="collsp.html#R1" title="COLLSP:pred.1">are_collinear</a>  &amp; <font color="Olive" title="b1">o</font>,<font color="Olive" title="b5">q1</font>,<font color="Olive" title="b7">q3</font> <a href="collsp.html#R1" title="COLLSP:pred.1">are_collinear</a>  &amp; <font color="Olive" title="b2">p1</font>,<font color="Olive" title="b6">q2</font>,<font color="Olive" title="b10">r3</font> <a href="collsp.html#R1" title="COLLSP:pred.1">are_collinear</a>  &amp; <font color="Olive" title="b5">q1</font>,<font color="Olive" title="b3">p2</font>,<font color="Olive" title="b10">r3</font> <a href="collsp.html#R1" title="COLLSP:pred.1">are_collinear</a>  &amp; <font color="Olive" title="b2">p1</font>,<font color="Olive" title="b7">q3</font>,<font color="Olive" title="b9">r2</font> <a href="collsp.html#R1" title="COLLSP:pred.1">are_collinear</a>  &amp; <font color="Olive" title="b4">p3</font>,<font color="Olive" title="b5">q1</font>,<font color="Olive" title="b9">r2</font> <a href="collsp.html#R1" title="COLLSP:pred.1">are_collinear</a>  &amp; <font color="Olive" title="b3">p2</font>,<font color="Olive" title="b7">q3</font>,<font color="Olive" title="b8">r1</font> <a href="collsp.html#R1" title="COLLSP:pred.1">are_collinear</a>  &amp; <font color="Olive" title="b4">p3</font>,<font color="Olive" title="b6">q2</font>,<font color="Olive" title="b8">r1</font> <a href="collsp.html#R1" title="COLLSP:pred.1">are_collinear</a>  holds <br/><font color="Olive" title="b2">p1</font>,<font color="Olive" title="b3">p2</font>,<font color="Olive" title="b4">p3</font>,<font color="Olive" title="b5">q1</font>,<font color="Olive" title="b6">q2</font>,<font color="Olive" title="b7">q3</font>,<font color="Olive" title="b8">r1</font>,<font color="Olive" title="b9">r2</font>,<font color="Olive" title="b10">r3</font> <a href="pascal.html#R1" title="PASCAL:pred.1">are_in_Pascal_configuration</a>  <span class="kw">by</span> <span class="lab"><a class="ref" href="pappus.html#T19" target="_self" onmouseover="rs('pappus/T19')" onmouseout="rh()">Th19</a></span>;<br/></div></div>
