Notes Over 4.8

1
Notes Over 4.8
Identifying Functions
A relation where each input has exactly one
output.
Function
Decide whether the relation is a function. If it
is a function, give the domain and the range.
1. Input Output
Not a function, because 4 goes to both 3 and 5
2
Notes Over 4.8
Identifying Functions
A relation where each input has exactly one
output.
Function
Decide whether the relation is a function. If it
is a function, give the domain and the range.
2. Input Output
Domain the input
Range the output
1, 2, 3, 4
1, 4, 9, 16
A function, because every input goes to only one
output
3
Notes Over 4.8
Identifying Functions
A relation where each input has exactly one
output.
Function
Decide whether the relation is a function. If it
is a function, give the domain and the range.
3. Input Output
1, 2, 3, 4
4, 6, 8
A function, because every input goes to only one
output
4
Notes Over 4.8
Identifying Functions
The equation y 3x 4 becomes f(x) 3x 4,
where the solution (x, y) becomes (x, f(x)).
Function Notation
Evaluate the function when x 3, x 0, x - 2.
5
Notes Over 4.8
Identifying Functions
The equation y 3x 4 becomes f(x) 3x 4,
where the solution (x, y) becomes (x, f(x)).
Function Notation
Evaluate the function when x 3, x 0, x - 2.
6
Notes Over 4.8
Identifying Functions
The equation y 3x 4 becomes f(x) 3x 4,
where the solution (x, y) becomes (x, f(x)).
Function Notation
Evaluate the function when x 3, x 0, x - 2.
7
Notes Over 4.8
Writing and Using a Linear Function
7. While on vacation, your family traveled 2040
miles in 6 days. Your average speed was
miles per day.
340
a. Write a linear function that models the
distance that your family traveled each day.
Verbal Model
Distance traveled
Average speed
Time
Labels
Distance traveled
f ( t )
Average speed
340 miles per day
Time
t days
8
Notes Over 4.8
Writing and Using a Linear Function
7. While on vacation, your family traveled 2040
miles in 6 days. Your average speed was 340 miles
per day.
b. Use the model to find the distance traveled
after 1.5 days of travel.
9
Notes Over 4.8
Writing and Using a Linear Function
7. While on vacation, your family traveled 2660
miles in 7 days. Your average speed was
miles per day.
380
a. Write a linear function that models the
distance that your family traveled each day.
10
Notes Over 4.8
Writing and Using a Linear Function
7. While on vacation, your family traveled 2660
miles in 7 days. Your average speed was 380 miles
per day.
b. Use the model to find the distance traveled
after 1.5 days of travel.
11
Notes Over 4.8