1. What is a Function?

2. Remember your ABC’s
On a distance vs. time graph, which letters were “walkable”?
What were some rules that made a letter “walkable”?

3. Relations and Functions
Relation: A relationship between sets of information
Function: A special type of relation in which there’s only one value of the independent variable for each value of the dependent variable
I.e. For each x-value there is only one y-value
Using the alphabet example, ALL the letters are relations but ONLY the walkable letters were functions
For one moment in time (x-value) you cannot be in two places (y-value)

4. Functions
The dependent variable is said to be a function of the independent variable.
y is a function of x; or y = f(x)
Functions can be represented:
In words
By a table of values
By a mapping diagram
By a graph
By a set of ordered pairs {(1,1),(2,4),(3,9)}
By an equation