Solving
Evaluate f(x) = 4 + x for f(4)
What letter, or values, are is the domain?
Domain are the x-values
Relation
TRUE or FALSE: The vertical line test can determine if a relation is a function
TRUE
XY-plane or coordinate plane
Evaluate g(x) = 2x - 5 for g(10)
g(10) = 15
What letter, or value, is the range?
The range are the y-values
What is one way we can represent relations?
Hint: there are 4 we talked about
Mapping
Graph on xy-plane
Table
Ordered Pairs
Each x-value in a function has exactly how many y-values?
only 1 y-value per x-value
An ordered pair is written as what?
(x,y)
Evaluate f(x) = 3 - 3x2 for f(2)
f(2) = 3 - 3*22
= 3 - 3*4
= 3 - 12
= -9
What is the domain of the relation below?
(4, 2), (3,1) (-5, 3)
Domain: {4, 3, -5}
RANDOM QUESTION!
WHAT IS THE 15th LETTER IN THE ALPHABET?
O
Translate the function into words:
4x + 8
"Four times a number plus eight"
A relation in which each input has exactly one output
Function
I am given two functions:
f(x) = 5x + 2
g(x) = 6x - 3
What is the difference f(2) - g(1)?
f(2) = 12
g(1) = 3
12 - 3 = 9
What is the range of the relation?
(1, 6), (3, -4), (5, 1), (2, 0)
Range: {6, -4, 1, 0}
Determine if the following relation is a function:
(7, 3), (8, 4), (7, 1), (-4, 3), (3, 4)
Not a function! 7 has two different y values, 3 and 1
(5, 6), (6, 2), (3, 4), (-5, 4), (2, 1), (10, 2)
Yes, each x value has only 1 y value
The order of operations needed to evaluate expressions
PEMDAS
Evaluate f(x) = -5x - 6 for f(y - 4)
f(y+4) = -5(y - 4) - 6
= -5y + 20 -6
= -5y + 14
What are the other words for domain and range?
Inputs (domain) and outputs (range)
Answers will vary:
Examples: (1, 2), (3, 4), (5, 6), (7,8)
Each x must only have one y!
Solve x - 8 = 10 for x
x = 18
What does the 2 in 42 mean?