Maxima
http://maxima.sourceforge.net/
Maxima is a system for the manipulation of symbolic and numerical expressions, including differentiation, integration, Taylor series, Laplace transforms, ordinary differential equations, systems of linear equations, polynomials, and sets, lists, vectors, matrices, and tensors. Maxima yields high precision numeric results by using exact fractions, arbitrary precision integers, and variable precision floating point numbers. Maxima can plot functions and data in two and three dimensions.
DMath
Dmaths est un logiciel qui s'intègre aux suites bureautiques OpenOffice ( libre ), StarOffice et NeoOffice ( Mac OS X ) et qui facilite l'édition de formules mathématiques et/ou scientifiques. Il permet également d'utiliser directement votre logiciel de dessin préféré et d'incorporer des graphes de fonctions dans un document.
GnuPlot
Gnuplot is a portable command-line driven interactive data and function plotting utility for UNIX, IBM OS/2, MS Windows, DOS, Macintosh, VMS, Atari and many other platforms. The software is copyrighted but freely distributed (i.e., you don't have to pay for it). It was originally intended as to allow scientists and students to visualize mathematical functions and data.
Graph
Graph is an open source application used to draw mathematical graphs in a coordinate system. Anyone who wants to draw graphs of functions will find this program useful. The program makes it very easy to visualize a function and paste it into another program.
Geogebra
GeoGebra is a free and multi-platform dynamic mathematics software for schools that joins geometry, algebra and calculus. It received several international awards including the European and German educational software awards.
SciLab
The open source platform for numerical computation.
