Absolute value functions and transformations.notebook

Absolute value functions and transformations.notebook
October 14, 2014
Absolute Value Functions and Graphs
Objective:
I can graph an absolute value function by performing transformations on the parent function f (x) = |x|.
Oct 12­3:13 PM
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Absolute value functions and transformations.notebook
October 14, 2014
Vocabulary
· The function f(x) = |x| is an absolute value function. · The highest or lowest point on the graph of an absolute value function is called the vertex.
· An axis of symmetry of the graph of a function is a vertical line that divides the graph into mirror images. An absolute value graph has one axis of symmetry that passes through the vertex. Oct 12­3:15 PM
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Absolute value functions and transformations.notebook
October 14, 2014
Absolute Value Function
· Absolute Value Function
· Vertex
· Axis of Symmetry
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Absolute value functions and transformations.notebook
October 14, 2014
Building the Absolute Value Function
The absolute value function is
defined by f (x) = |x|.
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Absolute value functions and transformations.notebook
October 14, 2014
This is the absolute value parent function.
Table
x
f(x)=lxl
y
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Absolute value functions and transformations.notebook
October 14, 2014
Parent Function
· V­shape
· It is symmetric about the y­axis (Axis of Symmetry)
· The vertex is the minimum point on the graph
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Absolute value functions and transformations.notebook
October 14, 2014
Translation
A translation is a transformation that shifts a graph horizontally or vertically, but doesn’t change the overall shape or orientation.
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Absolute value functions and transformations.notebook
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Absolute value functions and transformations.notebook
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Absolute value functions and transformations.notebook
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Absolute value functions and transformations.notebook
October 14, 2014
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Absolute value functions and transformations.notebook
October 14, 2014
Stretching and Compression
The graph of y = a|x| is graph of y = |x| vertically stretched or compressed depending on the |a|.
The value of a acts like the slope.
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Absolute value functions and transformations.notebook
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Absolute value functions and transformations.notebook
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Absolute value functions and transformations.notebook
October 14, 2014
Reflection
The graph of y = a|x| is graph of y = |x| reflected across the x­axis. Oct 12­3:39 PM
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Absolute value functions and transformations.notebook
October 14, 2014
y = ­a |x – h| + k
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Absolute value functions and transformations.notebook
October 14, 2014
Multiple Transformations
In general, the graph of an absolute value function of the form y = a|x – h| + k can involve translations, reflections, stretches or compressions.
To graph an absolute value function, start by identifying the vertex
Oct 12­3:50 PM
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Absolute value functions and transformations.notebook
October 14, 2014
Graphing Absolute Value Functions
Graphing y = a|x – h| + k is straight forward:
1. Plot the vertex (h, k). (note…if +h inside that means h is negative(to the left); if – h inside that means h is positive (to the right)
2. Use the a value as slope to plot more points. Remember you have to do positive and negative slope to get points on both sides of the V
3. Connect the dots in a V­shape.
Oct 12­3:50 PM
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Absolute value functions and transformations.notebook
October 14, 2014
Example 1
Graph the following function without making a table.
y = |x – 2| + 3 Vertex
How does this graph move?
Did this graph stretch or compress?
(slope of 1)
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Absolute value functions and transformations.notebook
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Absolute value functions and transformations.notebook
October 14, 2014
Example 2
Graph the following function.
y = (1/2)|x| Vertex
How does this graph move?
Did this graph stretch or compress?
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Absolute value functions and transformations.notebook
October 14, 2014
Your turn:
y = (3/2)|x| Vertex ( , )
Translations Slope
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Absolute value functions and transformations.notebook
October 14, 2014
Your turn:
y = 2|x + 2| ­ 3 Vertex ( , )
Translations Slope
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Absolute value functions and transformations.notebook
October 14, 2014
write an abs value function that...
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