Proofs through Exploration in Dynamic Geometry Environments

  • Constantinos Christou
  • Nikos Mousoulides
  • Marios Pittalis
  • Demetra Pitta-Pantazi


The recent development of powerful new technologies such as dynamic geometry software (DGS) with drag capability has made possible the continuous variation of geometric configurations and allows one to quickly and easily investigate whether particular conjectures are true or not. Because of the inductive nature of the DGS, the experimental-theoretical gap that exists in the acquisition and justification of geometrical knowledge becomes an important pedagogical concern. In this article we discuss the implications of the development of this new software for the teaching of proof and making proof meaningful to students. We describe how three prospective primary school teachers explored problems in geometry and how their constructions and conjectures led them “see” proofs in DGS.


dynamic geometry exploration functions of proof phases of proof proof 


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Copyright information

© National Science Council, Taiwan 2004

Authors and Affiliations

  • Constantinos Christou
    • 1
  • Nikos Mousoulides
    • 1
  • Marios Pittalis
    • 1
  • Demetra Pitta-Pantazi
    • 1
  1. 1.Department of Educational SciencesUniversity of CyprusNicosiaCyprus

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