Functions vs. Non-Functions

Front

What is a function?

Back

A function is a relation where each input (x-value) has exactly one output (y-value).

Tags

CCSS.8.F.A.1

Front

What is a non-function?

Back

A non-function is a relation where at least one input (x-value) has more than one output (y-value).

Tags

CCSS.8.F.A.1

Front

What is the vertical line test?

Back

The vertical line test is 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

Give an example of a function using ordered pairs.

Back

{(1, 2), (2, 3), (3, 4)} - Each x-value has one unique y-value.

Tags

CCSS.8.F.A.1

Front

Give an example of a non-function using ordered pairs.

Back

{(1, 2), (1, 3), (2, 4)} - The x-value 1 has two different y-values.

Tags

CCSS.8.F.A.1

Front

What does it mean for a mapping to represent a function?

Back

A mapping represents a function if every input has exactly one output.

Tags

CCSS.8.F.A.1

Front

Can a function have repeating x-values?

Back

Yes, but each repeating x-value must have the same corresponding y-value.

Tags

CCSS.8.F.A.1

Front

What is an example of a mapping that does not represent a function?

Back

A mapping where one input has multiple outputs, e.g., Input A -> Output 1, Output 2.

Tags

CCSS.8.F.A.1

Front

What is the definition of a relation in mathematics?

Back

A relation is a set of ordered pairs, which can show how two sets of values are connected.

Tags

CCSS.8.F.A.1

Front

How can you tell if a graph is a function?

Back

Use the vertical line test: if any vertical line crosses the graph more than once, it is not a function.