GRAPHING CALCULATOR TOOLS
Scientific Calulator is a powerful, programmable, scientific calculator.Some of its features include: Supports variables, constants, and custom functions; Save scripts online so you can access them anywhere or in a local library; Complex numbers, arbitrary precision integers, and exact fractions; Algebraic pretty-printed display; Full functional programming language; Supports matrix and vector operations; Calculation history lets you refer to previous results.
Graph.tk is an online and open-source graphing utility.It's very easy to use. Use the "+" button to create a new equation. Use "/" for fractions, "^" for exponentials, and "*" for multiplication.
GeoGebra (www.geogebra.org) is free dynamic mathematics software for all levels of education that brings together geometry, algebra, spreadsheets, graphing, statistics and calculus in one easy-to-use package. Interactive learning, teaching and evaluation resources created with GeoGebra can be shared and used by everyone at tube.geogebra.org.