Functions - identifying and notation

1. September 14, 2009
Warm ­ Up
Do you remember the
slope­intercept form of
a linear equation?
Use that form to find
the equation of the
graph to the right.

2. Functions
Polynomial Functions
Linear Functions
Quadratic Functions
Cubic Functions
Exponential Functions
Logarithmic Functions
Rational Functions
Radical Functions
Trigonometric Functions

3. What Makes a Function ­ Part 1
x y f (x)
Input Output
Domain Range

4. What Makes a Function ­ Part 2
A function is a relation where the input
value does not repeat (outputs can).

5. Function Notation
f (x) means "function of x"
NOT f times x !
y = mx + b
f (x) = mx + b
} mean same thing
Doesn't have to be "f". For example:
g(x) = mx + b
still mean the same thing
h(x) = mx + b

6. How to Use Function Notation
Evaluate the function when x = ­3
f (x) = x2 + 4x ­ 5 g(x) = 5x
h(x) = 7

7. HW: pg. 76 #1­13, 16­23, 34­39
Do HW on loose leaf
It will be collected