mathomatic seems to be a console-only program. It is ok for me to use console, but if i need it in an exam it would take too much time ...

Texmacs looks nice.

I will install it on my PC, and test it

I have a CASIO CFX-9850 GB Plus, which has no CAS.
lybniz goes to the right direction, but it is not effective enough for harder mathematic-calculation.

@Alfabeta You would kill for a word processor? I would kill for CAS