Function or Not a Function

Front

What is a function?

Back

A relation where every input (x-value) has exactly one output (y-value).

Front

What is the vertical line test?

Back

A method to determine if a graph represents a function; if a vertical line intersects the graph at more than one point, it is not a function.

Front

Is the set of ordered pairs {(1, 2), (2, 3), (3, 4)} a function?

Back

Yes, because each input has exactly one output.

Front

Is the set of ordered pairs {(1, 2), (1, 3), (2, 4)} a function?

Back

No, because the input '1' has two different outputs (2 and 3).

Front

What is a relation?

Back

A set of ordered pairs, which can include functions but is not limited to them.

Front

What does it mean for a relation to be not a function?

Back

It means that at least one input is associated with more than one output.

Front

Which of the following is a function: {(1, 2), (2, 3), (3, 3)} or {(1, 2), (1, 3)}?

Back

{(1, 2), (2, 3), (3, 3)} is a function; {(1, 2), (1, 3)} is not.

Front

What is an example of a function in real life?

Back

A vending machine: each button (input) corresponds to one specific snack (output).

Front

What is the definition of a linear function?

Back

A function that graphs to a straight line, typically in the form y = mx + b.

Front

What is an example of a non-function?

Back

A circle, because a vertical line can intersect it at two points.