Identifying Functions or Not

• Function 
• Not a Function

Is the relation a function? Why.

• Yes, because the x-value 11 has two y-values pair with it.

• Yes, because each x-value has only one y-value paired with it.

• No, because the x-value 11 has two y-values pair with it.

• No, because each x-value has only one y-value paired with it.

How do you use the vertical line test?

• Draw vertical lines through your graph. If any of the vertical lines you draw intersects the graph more than once then the graph is not the graph of a function.

• Draw vertical lines through your graph. If any of the vertical lines you draw intersects the graph more than once, then it is a function.

Is this mapping a function or not a function?

• Function; the x's don't repeat

• Not a Function; the x's repeat

Is this table a function or not a function?

• Function; the x's don't repeat

• Not a Function; the x's repeat

Which set of values is a function?

• (9,5) (10,5) (9,-5) (10,-5)

• (3,4) (4,-3) (7,4) (3, 8)

• (6,-5) (7, -3) (8, -1) (9, 1)

• (2, -2) (5, 9) (5, -7) (1, 4)

Is this graph a function or not a function?

• Function; it passes the vertical line test

• Not a Function; it fails the vertical line test

Which of these sets is not a function?

• { (2,3) , (3,5) , (4,9) }

• { (2,3) , (2,5) , (4, 9) }

• { (2,3) , (3,3) , (4,9) }

• Function; it passes the vertical line test

• Not a Function; it fails the vertical line test

Is this graph a function or not a function? 

• Function

• Not a Function