Function Grapher
Enter a function such as f(x) = x² + 1 or f(x) = sin(x) and view its curve on a coordinate grid. Use the graph to explore function behavior, compare examples, and understand how an expression changes across x-values.
Function graph and live controls
Evaluate a function
How to use the Function Grapher
-
Enter the function rule without writing f(x) =. For example, type
x^2 + 1. - Enter a numeric value for x.
- Select Evaluate f(x) to substitute the chosen value into the function.
- Read the result, then open the main Graphing Calculator to see the full curve.
Worked example: f(x) = x² + 1
Step 1: The function rule is f(x) = x² + 1.
Step 2: Replace each x with 3: f(3) = 3² + 1.
Step 3: Square 3 to get 9, then add 1. The final value is 10.
This is one point on the function. Evaluating other x-values gives other points that together form its graph.
Graph this function →How the function graph works
A function rule maps each x-value to a y-value. For example, y = x^2 makes a U-shaped parabola, while y = sin(x) creates a repeating wave. Enter a rule with the scientific keyboard; the curve updates on the coordinate plane. Drag to pan, use the mouse wheel or touch controls to zoom, and use radians for trigonometric functions.
Why Use a Function Grapher?
A function grapher is useful when you want to connect an algebraic rule with the shape it creates. It can help students explore linear, quadratic, and trigonometric functions, compare example curves, and build intuition about how outputs change as x changes. Graphly Math provides a visual place to test an expression and inspect its behavior without drawing every point by hand. This can support homework review, classroom demonstrations, and independent revision. Try changing one part of a function at a time and observe the effect on the graph. Treat the display as a learning aid and confirm important conclusions with algebraic reasoning.