Function Graph Plotter — Plot Math Functions
Enter up to 3 math functions and see them plotted on an interactive graph with grid, axes, and coordinate tracking. Supports polynomials, trigonometric functions, square roots, logarithms, and more.
How to Use the Function Graph Plotter
A function graph shows the relationship between an input value (x) and an output value (y). When you enter a mathematical expression like x^2, the plotter evaluates that expression for hundreds of x-values across the visible range and draws the resulting curve on a coordinate grid. This visual representation makes it easy to spot key features — where a function crosses the x-axis (roots), its highest and lowest points (maxima and minima), and how it behaves as x gets very large or very small.
Supported Functions
You can use standard arithmetic operators (+, -, *, /), exponents (x^2, x^3), and these built-in functions: sin(x), cos(x), tan(x), sqrt(x), abs(x), log(x) (natural log), and exp(x). You can also use constants like pi and e. Combine them freely — for example, sin(x)*x^2 or sqrt(abs(x)).
Reading a Function Graph
The horizontal axis represents x (the input) and the vertical axis represents y (the output). Where the curve crosses the x-axis, y equals zero — these are the roots or zeros of the function. Where the curve crosses the y-axis, x equals zero — this is the y-intercept. Steeper sections mean the function is changing rapidly; flatter sections mean it is changing slowly. Hover over the graph to see exact coordinates at any point.
Why Plot Multiple Functions?
Comparing functions visually reveals relationships that are hard to see from equations alone. You can see where two functions intersect (their solutions are equal), which one grows faster, and how transformations like shifting or scaling change a curve. Plotting up to three functions simultaneously makes this kind of comparison quick and intuitive.
Zooming and Exploring
Use the Zoom + and Zoom − buttons or type custom X Min/Max values to focus on a specific region. Zooming in reveals fine detail around roots and turning points. Zooming out shows the big-picture behavior of the function. This is especially useful for functions like sin(1/x) that have interesting behavior near the origin.