1. Bellringer

2. Relations and Functions Woohoo!!!
Chapter 5 Section 2
Relations and Functions
Woohoo!!!

3. Some key terms Relation- a set of ordered pairs
Domain- the set of first coordinates, the x’s
Range- the set of second coordinates, the y’s

4. Functions
Function- a function is a relation in which each member of the domain is paired with exactly one member of the range
In other words… you can not have a domain (x value) repeat itself
Vertical Line Test- If any vertical line passes through no more than one point of the graph of a relation then the relation is a function

5. How to tell if it is a function
Since each element of the domain is paired with exactly one element of the range this is a function. Also, notice no x values are repeated

6. How to tell if it is a function
This is called a mapping. It shows the relation between each x and y value
It does not matter that the y values are shared as long as the x value is not repeated or shared this is a function X 2 3 5 Y 3

7. Functional notation An equation looks like this
y = 3x + 5
This same equation written in functional notation looks like this
f(x) = 3x + 5
We simply replace y with f(x)

8. Finding functional value
If f(x) = 2x +3 find each value.
f(4)
f(x) = 2x +3
f(4) = 2x +3
f(4) = 2(4) +3
f(4) = 8 +3
= 11
f(6a)
f(x) = 2x +3
f(6a) = 2x +3
f(6a) = 2(6a) +3
f(6a) = 12a +3
= 12a +3

9. Your Turn
If g(x) = 3x - 7 find each value.
g(2h)
6h - 7
g(-2)
-13

10. Assignment
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