GDI
The goal: an intelligent dynamic geometry program -able to simulate on the computer the ruler and compass paradigm -able to drag elements on constructions while keeping established relations among geometric objects -omniscent (as a teacher!!) regarding facts about the geometric constructions -enhanced features (geometric locus, 3D, web access, etc.) First versions around 2000
Authors: F. Botana http://webs.uvigo.es/fbotana/ J.L. ValcarceSeveral similar and recent attempts...Geometry Expert, Cinderella, Geother...but, of course, GDI is endowed with some unique features...• Given a triangle ABC, a point X, its symmetrical points with respect to the sides, say, M,N,P, ....... then points M, N, P are they aligned?