Cadabra - Cadabra is the name of a universal computer algebra system designed for those users looking for the solution to problems encountered in the filed theory.
Maxima - Maxima is a fairly complete computer algebra system written in Lisp with an emphasis on symbolic computation.
Wolfram Mathematica - Mathematica has characterized the cutting edge in specialized processing—and gave the chief calculation environment to a large number of pioneers, instructors, understudies, and others around the globe.
SMath Studio - Tiny, powerful, free mathematical program with WYSIWYG editor and complete units of measurements support.
Mathomatic - Mathomatic is a free general purpose computer algebra system that is an expert in solving and simplifying the algebraic and computation issues.
GeoGebra - GeoGebra is free and multi-platform dynamic mathematics software for learning and teaching.