The document discusses functions and relations. It defines a function as a set of ordered pairs where each x-value is paired with only one y-value. A relation is a function only if each x-value is paired with exactly one y-value; if an x-value is paired with more than one y-value, it is not a function. It then asks the reader to identify which of several relations presented are functions based on this definition. It also gives some examples of evaluating simple functions.

2. •The first elements in the ordered pairs (the xvalues), form the domain. The second
elements in the ordered pairs (the y-values),
form the range. The range is the
dependent variable.
Example:
(9,2)

3. Function: A function is a set of ordered pairs in which
each x-element has only ONE y-element associated
with it.
If it intersects in one point it’s a function.
If more then it’s not a function.

8. how fast
The car
travels

12. Which relations below are functions?
Relation #1 { (-1,2), (-4,51), (1,2), (8,-51) }
Relation #2 { (13,14), (13,5) , (16,7), (18,13) }
Relation #3 { (3,90), (4,54), (6,71), (8,90) }
Which relations below are functions?
Relation #1 { (3,4), (4,5), (6,7), (8,9) }
Relation #2 { (3,4), (4,5), (6,7), (3,9) }
Relation #3 { (-3,4), (4,-5), (0,0), (8,9) }
Relation #4 { (8, 11), (34,5), (6,17), (8,19) }

13. Given f (x) = 3x + 7, find f (5).
D
D
D
D
D
D
Choose:
15
22
42

14. Use functional notation to describe
the function displayed at the right.
D
D
D
D
D
D
Choose:
f (x) = 2x
f (x) = x²
f (x) = x + 2
x
-3
-2
-1
0
1
2
3
y
9
4
1
0
1
4
9

15. A challenge question
Larry's father has five sons named Ten, Twenty, Thirty,
Forty...Guess what would be the name of the fifth???