Post on 18-Jan-2016
2.8 Absolute Value Functions
Goals:
To graph absolute value functions
To identify transformations of absolute value functions.
Graphing on TI-83/84 Press Y= Enter equation into
Y= screen For absolute value,
press MATH-RightArrow-1
Be sure to close off parentheses
The general absolute value equation:
y a x b c if -, then Reflection Across the X-axis (RAX)
if a > 1, vertical shrink by a factor of a.
if a < 1, vertical stretch by a factor of a.
if + b, horizontal shift left b.
If – b, horizontal shift right b.
if + c, vertical shift up c.
If – c, vertical shift down c.
Graphing Absolute Value Functions
Graph the vertex Plot two points on either side of the
vertex Use the slope/plug it in and the fact that
the graph is symmetric Connect three points to make a v-
shaped graph
3 33 3
2 11 1
1 34 2
4 4
Domain Range Domain Range
21
3y x
What are the transformations of the following equations?
1)
2)
4 10 3y x
2 5y x
7 14y x
3)
4)
h. shift right 2
v. shift up 5
RAX
h. shift left 7
v. shift down 14
v. stretch by a factor of 2/3
h. shift left 1
RAX
v. shrink by a factor of 4
h. shift right 10
v. shift down 3
Graph the function – name 3 pointsGraph the function – name 3 points
1) y x
x y
Graph the function – name 3 pointsGraph the function – name 3 points
2) y x
x y
Graph the function – name 3 pointsGraph the function – name 3 points
3) 2y x
x y
Graph the function – name 3 pointsGraph the function – name 3 points
4) 3 1y x
x y
State the transformations and then graph the function
Transformations:12 3
2y x
x y
Homework
p. 126
18-25 all
34-36 all