Graph Plotter
Type up to three functions of x. Drag to move around, scroll or pinch to zoom, and the key points are listed under the graph.
Use x as the variable, for example x^2 - 4, sin(x), 2x + 1 or sqrt(x). Trig uses radians.
Key points
Key points are found in the part of the graph you can see.
About this tool
This graph plotter draws up to three functions of x on the same axes, each in its own colour. Type something like x^2 - 4, sin(x) or 2x + 1 and the curve appears straight away. The plotter lists the x-intercepts, the y-intercept and any points where your graphs cross, so you can check sketches, solve equations graphically and see how changing a number changes the shape.
Tips
- Trig functions use radians, so sin(x) crosses the x-axis at multiples of pi (about 3.14), not at 180.
- Roots and intersections are only found in the part of the graph you can see. If you expect one that is not listed, zoom out or pan.
- With the graph focused, the arrow keys pan and the + and - keys zoom, so you can explore without a mouse.
FAQ
- How do I type functions?
- Use x as the variable and ^ for powers: x^3 - 2x + 1. You can write 2x instead of 2*x. Trig functions are written with brackets, for example sin(x) or cos(2x).
- What do the roots and intercepts tell me?
- The roots (x-intercepts) are the solutions of f(x) = 0. For y = x^2 - 4 they are x = -2 and x = 2, and the y-intercept is (0, -4). Intersections between two graphs are the solutions of f(x) = g(x).
- Why does it use radians?
- Radians are the standard angle measure for graphs of trig functions, so sin(x) completes one full wave between 0 and 2pi. If your worksheet uses degrees, remember that 180 degrees is pi radians.