8. Functions or Relations? relation
function
Identify the domain and range of each.
relation
DOMAIN
(3, 2), (2, 3), (3, 3)
RANGE
function
(1, 4), (4, 1), (-1, 4)
DOMAIN
RANGE
relation
(-5, 2), (0, 2), (-5, 3) DOMAIN
RANGE
function
(5, -2), (3, 2), (6, 2) DOMAIN
RANGE
9. Example 1
An example of a relation, that is a function is:
x y
-2 -4 y=x-2
-1 -3
0 -2
1 -1
2 0
An example of a relation, that is NOT a function is:
xy
-3 -4
x 2 + y 2= 25
-3 4
0 -5
05
43
What's The Verticle Line Test?
10. The Verticle Line Test
Sweep a vertical line across the
graph of the function. If the line
crosses the graph more than
y = x2 once it is not a function, only a
relation.