Identifying Functions

Front

What is a function?

Back

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

Front

Which of the following sets of ordered pairs represents a function? {(9,5), (10,5), (9,-5), (10,-5)}

Back

Not a function because the x-value 9 has two different outputs.

Front

Which of the following sets of ordered pairs represents a function? {(3,4), (4,-3), (7,4), (3, 8)}

Back

Not a function because the x-value 3 has two different outputs.

Front

Which of the following sets of ordered pairs represents a function? {(6,-5), (7, -3), (8, -1), (9, 1)}

Back

This is a function because each x-value has a unique y-value.

Front

Which of the following sets of ordered pairs represents a function? {(2, -2), (5, 9), (5, -7), (1, 4)}

Back

Not a function because the x-value 5 has two different outputs.

Front

What does it mean for a relation to be a function?

Back

It means that for every input, there is only one corresponding output.

Front

If a relation has the ordered pairs (1,2), (2,3), (3,4), is it a function?

Back

Yes, because each x-value is unique.

Front

If a relation has the ordered pairs (1,2), (1,3), (2,4), is it a function?

Back

No, because the x-value 1 has two different outputs.

Front

What is the vertical line test?

Back

A method to determine if a graph represents a function; if a vertical line crosses the graph more than once, it is not a function.

Front

Can a function have the same output for different inputs?

Back

Yes, a function can have the same output for different inputs, as long as each input has only one output.