Sage

Need help with geometry, algebra or any other number calculations? Sage is a helpful tool you can download for free and serves as a great open source alternative to commercial mathematics softwares like Mathlab and Mathematica. It can help you with any or almost all of your calculating needs. This helpful program was initially released in 2005 under a GNU Public License. As mentioned, it can help you with pretty much anything you might need when numbers are involved. From "algebra, calculus, elementary to very advanced number theory, cryptography, numerical computation, commutative algebra, group theory, combinatorics, graph theory, exact linear algebra and so much more," the program is your one-stop-shop for all of your computation needs.