Geometry Expert (GEX)

Geometry Expert (GEX) is a software system for automated geometry theorem proving-discovering and geometric constraint solving.

  1. GEX is a powerful computer program for geometric reasoning. Within its domain, it invites comparison with the best of human geometry provers. It implements most of the effective methods for geometric reasoning introduced in the past twenty years, including the deductive base method, Wu's method, the area method, the Groebner basis method, the vector method, and the full-angle method. With these methods, users may automated prove geometry theorems, to discover new properties of theorems, and to generate readable proofs for many geometry theorems.

  2. A variant of GEX: MMP also implements several state of the art methods for geometric constraint solving, that is, the user can input the geometric properties satisfied by a geometric diagram, and the software will automatically generate a constructive way to draw the diagram. Geometric constraint solving is a key property of so-called intelligent computer-aided design (CAD).

  3. GEX is also a dynamic geometry software, and can be used to build dynamic visual models to assist teaching and learning of various mathematical concepts. By dynamic visual models, we mean models built by computer softwares that can be changed dynamically. With GEX, we can build four classes of dynamic visual models: geometric transformations, loci generation, diagrams of functions, and loci generation.

Documents and Softwares

  1. An introductory paper for GEX can be obtained here
  2. An experimental Windows version of GEX, with a set of examples, can be obtained here

Java Geometry Expert

Java GEX is an internet based version of Geometry Expert.


MMP/Geometer is a new Chinese version of GEX with ability of automated geometric diagram construction.

References for Automated Geometry Reasoning

References for Geometric Constraint Solving

Using GEX for Mathematics Instruction