Xcas is a user interface to Giac, a free, basic Computer Algebra System (CAS) for Windows, macOS and Linux/Unix. Giac can be used directly inside other C++ programs. Xcas/Giac is an open-source project developed by Bernard Parisse’s et al. at the Joseph Fourier University of Grenoble (Isère) since 2000. It is based on experiences gained with Parisse’s former project Erable. Giac has a compatibility mode with Maple and MuPAD software and TI-89, TI-92 and Voyage 200 calculators. Users can use Giac/Xcas as

Source: Xcas – Wikipedia