Question

What is a function rule?

Answer 1

Function rule:

• The function rule is the relationship between the input or domain and the output or range.
• A relation is a function if and only if there exists one value in the range for every domain value.
• A function is written as $f\left(x\right)$, where $x$is the input value.
• The general form of a function is $y=f\left(x\right)$
• A vertical test is done graphically to determine whether the relation is a function or not.

A vertical line is drawn anywhere on the function. If it intersects the function only at one point, it is a function. If the line intersects at more than one point, it is not a function.