A computer algebra system (CAS) is a program which is able to carry out various symbolic manipulations with mathematical expressions. Some well-known computer-algebra systems are Mathematica, Maple, Wolfram Alpha, GAP, SAGE. Questions on this site about computer algebra systems should be mathematical in nature, and not just about the syntax or the mechanics of the CAS. Otherwise the question would be better suited for a different Stack Exchange site.
A computer algebra system (CAS) is a program which is able to carry out various symbolic manipulations with mathematical expressions. Typically they include simplification, differentiation, integration, solving equations etc.
Some well-known computer-algebra systems: Mathematica, Maple, Wolfram Alpha, GAP, SAGE.
Some of them have also separate tags: mathematica, maple, wolfram-alpha, gap, sage
For Mathematica there is even a separate Stack Exchange site. Another related site is Computational Science (currently in beta).
