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States that a line bisects the angle spanned by three points. That is, if line_angular_bisector_of_three_points(l,p,q,r) then l is the line that passes through q and bisects the angle pqr.

Pathological cases:

  • If all three points are the same, behaviour is undefined.
  • If p and r are the same point, different from q, then the bisector is the line which passes through all of them.
  • If q is the same point as one of p or r, and different to the other, then the behaviour is undefined (secuences could be constructed where the limit is the common line or its perpendicular through q).