1. VOCABULARY! EXAMPLES!
Relation:
Domain:
Range:
Function:
Functions can be represented by:
Graphs Tables Mappings Ordered Pairs Function Rules
A set of ordered pairs
The set of all the input (x) values
The set of all the output (y) values
A special relation that has exactly ONE output for each input (or exactly ONE y value for each x value)
( , )
f(x) = 2x + 1
g(x) = 4x
h(x) = x2 -1
Input
Output

2. Input-Output Tables Mappings
By looking at each input-output table or mapping, tell whether or not the relation is a function.
If it is a function, state the domain and range.
Input-Output Tables Mappings 3.
Input
Output x y x y

3. VERTICAL LINE TEST GRAPHS can represent functions.
The ____________________ ___________ __________ can help you test whether or not a graph is a function.
Remember: There can only be ONE y value for each x value. If you run your pencil across two points vertically above one another, it is NOT a function!
Determine
which
graphs
are
functions
Can the graph of a function be a horizontal line? A vertical line? Explain why or why not.
VERTICAL LINE TEST