Definition
Function graph
A function graph plots every allowed input with its matching output as a point.
View exact chart data
| x | y |
|---|---|
| -2 | -3 |
| -1 | -1 |
| 0 | 1 |
| 1 | 3 |
| 2 | 5 |
What it means
Take one input and find the output made by the function. Put the input across the grid and the output up the grid. That makes one point. Plot every allowed pair, and the collection of points is the function graph.
Remember it
Input goes across; output goes up. Each pair lands on one point.
Example
For the rule “add 1” and allowed inputs 0, 1, 2, and 3, the outputs are 1, 2, 3, and 4. The function graph has the points (0, 1), (1, 2), (2, 3), and (3, 4).
Watch for
A function graph is not always a straight line. One input also cannot have two different output points in the same function.
Common mix-up
The graph is not just a sketch of the rule; it is the full set of plotted input-output pairs for the chosen domain.
Exact meaning
A function graph is the set of points for all allowed input-output pairs of a function; each point has coordinates (input, output).