1. Functions: Building Blocks of Mathematical Models
Chapter 9 Unit A
Functions: Building Blocks of Mathematical Models

2. Essential Question Where do we see function in our lives?
What are the key components of a function?

3. Key Components of Functions
Definition: describes how a relationship changes with respect to one more variables
Dependent: output, usually y or f(x)
Independent: input, usually x
Domain: values that make sense and are of interest to the independent variable (x)
Range: values of the dependent variable that corresponds to values of the domain

4. Example: Blowing up a beach ball
Independent variable: ________________
Dependent variable: __________________
Domain: ____________________
Range: _____________________
We can write ___________ as a function of _________, and is denoted as ___________.

5. Example: Coconut Tree
Coconut tree will produce 75 coconuts a year, but it takes 6 years to start producing.
Is this a function?
What are the independent and dependent variable?
What is the domain and range?
Make a table to represent 7 years

6. Example: Cell Phone
A cell phone company charges a phone activation fee of $20 and a monthly fee of $50/month.
Is this a function?
What are the independent and dependent variable?
What is the domain and range?
Write an equation to represent this situation

7. Example: Robbery Rate What is independent and dependent variable?
What is the
Domain and
Range?

8. How do you represent a function?
Data table (coconut tree example)
Picture or graph (Honolulu robbery example)
Equation or formula (cell phone example)

9. Classwork and homework:
DO NOW
D10: Present p.472 #44 (no need write paragraph)
Find 3 recent news stories
Identify independent and dependent variable
One example cannot use time as independent variable
HOMEWORK:
D9: Chapter 9 Unit A Quick Quiz p.469 #1-10