Microsoft Mathematics 4.0 includes a full-featured graphing calculator. It’s designed to work just like those expensive handheld calculators and it’s optimized for algebra, trigonometry, statistics, and calculus. Additional math tools help you solve systems of equations, evaluate sides and angles in a triangle, and convert from one system of units to another. It also has a quick reference library of formulas commonly used in mathematics, chemistry, and physics.
And another one here: