This document discusses relations and functions in mathematics. It defines a relation as a correspondence between two things represented as a set of ordered pairs, with the first element called the domain or independent variable and the second called the range or dependent variable. It states that for a relation to be a function, each element in the domain can only be paired with one element in the range, otherwise it would be "cheating". It also lists different ways relations and functions can be represented, including tables, mapping diagrams, graphs, and ordered pairs.

1. Relations and
Functions
Kelley Wood
MEDT 7477
Dr. Cooper
Fall 2012

2. What is a Relation?
A RELATION in math is what you would
think of when you here the word relationship
referring to people.
It’s a correspondence between two things.

3. In Math:

4. A relation is listed as a set of
ordered pairs. We’re familiar with
x- and y-values in an ordered
pair, but we learned some new
vocabulary words that refer to
these by different names.

5. D.I.X.I
This is Dixi – She’s the X-value.
Her name is an acronym.
Domain
Input
X Value
Independent Variable

6. R.O.Y. – D.
This is Roy D – He’s the yvalue.
His name is an acronym.
Range
Output
Y Value
Dependent Variable

7. A Function is a Relation

10. In order for a relation to be
a function, Dixi cannot
cheat on Roy-D.

11. There are various ways to
represent relations. Listen
as Ms. Grajkowske explains
the different ways.

13. Did you notice those
relations were not
functions? Well they
weren’t because -2 in the
domain was paired up with
2 and -2 in the range.
That’s CHEATING!!!!

14. Remember in order for a
relation to be a function,
each element in the domain
can be paired with only one
element in the range.

15. To Recap: Different Ways to Represent
Relations/Functions
Table
Mapping Diagram
Graph
Ordered Pair