Use Inverse Functions When two functions are inverses, they have a special relationship.
3.4 Use Inverse Funcons •
Inverse Funcons
•
Composites of Inverse Funcons
•
Four steps to finding an inverse funcon
1. They switch domains and ranges. 2. Their composites are equal to x.
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Use Inverse Functions
Use Inverse Functions
When two relations are inverses, they switch their domain and range. Which means they switch their xvalues and y values. Original Relation
x y
2 3
1 4
3 0
6 1
10 8
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Use Inverse Functions
Use Inverse Functions
Original Relation
x y
2 3
1 4
3 0
6 1
10 8
4 1
0 3
1 6
8 10
Inverse Relation
x y
3 2
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Algebra 2 Ch 3.4 Use Inverse Functions .notebook
Use Inverse Functions When relations are inverses, they are reflective over the line y=x.
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Use Inverse Functions If you are given an equation, you can find its inverse.
The inverse of
is
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Use Inverse Functions
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Use Inverse Functions Steps for Finding the Inverse of a Function
Find for .
1. Replace 2. Switch
We will use a four step process to find the inverse of a function.
and
3. Solve for 4. Replace
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Use Inverse Functions 1. Replace
with
with
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Use Inverse Functions
with 2. Switch
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and
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Algebra 2 Ch 3.4 Use Inverse Functions .notebook
Use Inverse Functions
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Use Inverse Functions
3. Solve for 4. Replace
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Use Inverse Functions
with
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Use Inverse Functions
Further Simplification of the Problem
Find for
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Use Inverse Functions 1. Replace
with
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Use Inverse Functions 2. Switch
and
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Algebra 2 Ch 3.4 Use Inverse Functions .notebook
Use Inverse Functions 3. Solve for
Use Inverse Functions 3. Solve for
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Use Inverse Functions 4. Replace
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Use Inverse Functions
with
Find for
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Use Inverse Functions 1. Replace
with
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Use Inverse Functions 2. Switch
and
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Algebra 2 Ch 3.4 Use Inverse Functions .notebook
Use Inverse Functions 3. Solve for
Use Inverse Functions 3. Solve for
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Use Inverse Functions 4. Replace
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with
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Use Inverse Functions Example #3 from the book on page 191. An elastic band's resistance R in pounds can be modeled by:
where L is the total length of the stretched rubber band in inches. • Find the inverse of the model. • Use the inverse function to find the length at which the band provides 19 pounds of resistance.
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Use Inverse Functions 1. Skip step #1
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Use Inverse Functions 3. Solve for
2. Skip step #2 3. Solve for
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Algebra 2 Ch 3.4 Use Inverse Functions .notebook
Use Inverse Functions
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Use Inverse Functions
4. Skip step #4
Now solve for The rubber band stretches 64 inches when 19 pounds of force is applied to it.
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Use Inverse Functions
What happens when you make a composite out of inverse functions?
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Use Inverse Functions
Find:
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Use Inverse Functions The two functions below are inverses, find their composites, f(g(x)) and g(f(x)).
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Use Inverse Functions
Find:
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Algebra 2 Ch 3.4 Use Inverse Functions .notebook
Use Inverse Functions
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Use Inverse Functions
The composite of inverses is always equal to x.
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Use Inverse Functions
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Use Inverse Functions When two functions are inverses, the domain of the inner function becomes the range of the outer function.
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Use Inverse Functions
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Use Inverse Functions
Are and inverses?
You need to find the composites of the functions to prove if they are inverses or not.
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Algebra 2 Ch 3.4 Use Inverse Functions .notebook
Use Inverse Functions
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Use Inverse Functions
They are not inverses, because the composite is not equal to x. You do not have to find the other composite.
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Use Inverse Functions
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Use Inverse Functions
If
Find: This just proved what we already knew.
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Use Inverse Functions
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Use Inverse Functions
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Algebra 2 Ch 3.4 Use Inverse Functions .notebook
Use Inverse Functions Since
Then
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Use Inverse Functions
Horizontal Line Test is its own inverse.
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Use Inverse Functions
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Use Inverse Functions
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The horizontal line test will tell you if the inverse of a function is itself a function.
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Use Inverse Functions
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Use Inverse Functions
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Algebra 2 Ch 3.4 Use Inverse Functions .notebook
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Use Inverse Functions 3.4 Use Inverse Funcons •
Inverse Funcons
•
Composites of Inverse Funcons
•
Four steps to finding an inverse funcon
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Attachments
Algebra 2 Ch 3.4 Inverse Functions, inverse of itself.gsp