1. Functions Relation such that each element x in a set A maps to EXACTLY ONE element y in a set B  Set A: Domain = set of all numbers for which the formula makes sense and defines real numbers (x values)  x = independent variable  Set B: Range = f(x) = set of all possible f(x) as x varies through the domain (y values)  y = dependent variable

2. Example

4. Vertical Line Test  A curve in the xy-plane is the graph of a function of x if and only if NO vertical line intersects the curve more than once  If any vertical line hits more than one point, the graph is not a function

5. Example Homework: p. 14 #1, 3, 11, 15, 29

6. Even v. Odd Functions

7. Function Guide

8. XY 00 11 21.4 31.7 42 XY -22 1 00 11 22

9. XY -24 1 00 11 24 XY -2-8 00 11 28

10. Composition of Functions

11. Piecewise Defined Functions XY 00 0.50 0.90 11 “Step Function”

12. Examples Homework: p. 14 #9, 31, 41-47 odd

13. Graph and Turn In for 20 Points