1. Algebra 1 Functions 2 Expression functions using function notation
Recall: A function describes the relationship between two quantities.
The distance you travel when your speed is 50 mph depends upon the time you spend traveling.
d =50t
Function Notation is used to show the relationship between two quantities.
d(t) = 50t
Distance is a function of time
Distance d is the dependent variable
Time t is the independent variable
Write using function notation The area of a circle is a function of its radius A = πr2 Your income is a function of your sales I = .05s

2. Describe the functional relationship indicated Indicate the independent variable and the dependent variable
C(r) = 2πr
v(s) = s s

3. Functional notation is used to evaluate a function for a given value
Find the value of f when x = 3
f(x) = x2 + 2x - 4
If g(x) = 5x – 3, find:
g(4)
g(-5)
g(7)

4. When a ball is thrown upward, its height h (in ft) is a function of the time t (in sec) that it is in the air. The height is given by h(t) = -16t2 + 48t + 4
Find the height of the ball after:
1 second
2 seconds
3 seconds
What are the dependent and independent quantities?

5. The volume v of a cylinder with a height of 8 inches and a radius of r is given by v(r) = 8πr2.
Explain the meaning of v(3) =
Explain the meaning of v(1) = 25.12
What are the dependent and independent variables?

6. Assignment: Worksheet