# HP Prime CAS

HP Prime uses the Giac/Xcas Version 1.1 Engine. Giac/Xcas is an open source CAS (Computer Algebra System) project initiated by Bernard Parisse from Institut Fourier (University of Grenoble I, France).

Giac is a C++ library that has types for symbolic algebraic manipulations. Xcas is a GUI (Graphical User Interface) linked with Giac that provides the functionalities of a general purpose CAS.

Project Background: The Giac/Xcas project began in year 2000, following the development of the CAS for HP graphing calculators. It has around 150,000 lines of C++ code which was mostly written by Bernard Parisse. Current development directions include faster algorithms for the mostly used operations: multiplication, division, gcd of multivariate polynomials.

Using Giac/Xcas:

```
factor(x^4-1); cfactor(x^2+1);
normal((x+1)^4) solve(x^2-3*x+2=0);
csolve(x^2=2*i);
solve([x+y=1,x-y=3],[x,y]) simplify(sin(3x)/sin(x));
gcd(x^4-1,x^3-1) f(x):=sin(x^2):;
f(sqrt(pi)); f'(2);
f'(y) int(1/(x^4-1));
int(1/(x^4+1)^4,x,0,+infinity) limit(sin(x)/x,x=0);
series(sin(x),x=0,5);
A:=[[1,2],[3,4]];
inv(A);
det(A-x*idn(A));
A[0,0];
rref(A);
eigenvalues(A);
eigenvectors(A);
```