1. 3.2 Functions

2. Functions
Relation: any set of ordered pairs (x, y) Domain: set of x-values Range: set of y-values Function: relation where x-values don’t repeat On a graph, it passes the vertical line test Written:

3. Ex 1) Relation: {(–1, 0), (0, –1), (1, 0)}
Domain: { –1, 0, 1}
Range: { –1, 0}
Function?
YES! (x’s don’t repeat)
Ex 2) Is the relation a function?
p = {(x, y) │ x = –2}
No! Fails vertical line test!
Don’t repeat yourself!

4. Finding the domain & range of an equation:
Domain: look for any restrictions on x
(y must be real)
x under radical
x in denominator of fraction

5. Finding the domain & range of an equation:
Range: look for any restrictions on y
(using known domain)
Draw a quick sketch if need to or use graphing calculator

6. Ex 3) Find domain & range of
Range: y is only positive
(square of negative is positive)
All Real Numbers
Interval Notation:

7. Ex 4) Find D & R of Domain: term under radical must be ≥ 0
Range: under radical ≥ 0

8. Find:
Ex 5)
Ex 6)
Ex 7)
Ex 8)

9. Homework
#303 Pg – 43 odd