Xcas

Xcas is a user interface to Giac, which is an open source[2] computer algebra system (CAS) for Windows, macOS and Linux among many other platforms.

Xcas has compatibility modes with many popular algebra systems like WolframAlpha,[4] Mathematica,[5] Maple,[6] or MuPAD.

Among other things, Xcas can solve differential equations (Figure 3) and draw graphs.

[25] Xcas and Giac are based on experiences gained with Parisse's former project Erable.

The system was also chosen by Hewlett-Packard as the CAS for their HP Prime calculator, which utilizes the Giac/Xcas 1.5.0 engine under a dual-license scheme.

calculate fractions without common denominator
Figure 1. Xcas calculates fractions without common denominator.
Figure 2. Xcas can solve equations, calculate derivatives, antiderivatives and more.
Figure 3. Xcas can solve differential equations.