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  A few topics from Geometry \  \_\_

<pre>
Objects.

Points - A,B,C, ...
Lines  - a,b,c, ...
Planes - \^al, \^be, \^ga, ...
Relations:
   \^.bi  
   =
   ~  "congruent"
   between

Axioms.

  1. For any two distinct points A an B, there exists unique line b
     such both A and B belong this line.

     \^.faA, \^.faB, , A\^.neB \^.exa  A\^.bia and B\^.bia 
     and
     \^.faa, \^.fab, \^.faA, \^.faB,  
     if      A\^.bia, B\^.bia,
             A\^.bib, B\^.bib,
     then    a = b.
  
  2. Betweeness. 
     For any three distinct points A, B, C lying on the same line, 
     there only one of following "prepositions" can be true:
 
         A is between B and C
         B is between A and C
         C is between A and B.


Example.

     Set: {A,B,C} 
     Sets a={A,B}, b={B,C}, and c={C,A} are lines.




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