A27­7Notes.notebook
March 29, 2016
Algebra 2
Ch.7 Notes Page 42
P42 7­7 Inverse Relations and Functions
Aug 19­6:20 AM
Inverse Relations
Relations are ordered pairs (a , b)
The Domain is a ­ The Range is b
Inverses switch the order of the relation to (b , a)
The Domain is b ­ The Range is a
Not a Function
(2 y values for each x)
Nov 8­8:59 AM
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A27­7Notes.notebook
March 29, 2016
Inverse Relations are Reflections over y = x
Nov 13­8:11 AM
Finding Inverse Relations
Find the Inverse of...
y = x2 + 3
1. Interchange x and y
2. Solve for y
Graph is a Reflection over y = x
Nov 13­8:14 AM
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A27­7Notes.notebook
March 29, 2016
Finding Inverses of Functions
The Inverse of function f is f ­1 and is called "f inverse."
f(x) is used for functions, but the relation f ­1 may not be a function.
f(x) = √(x + 1) 1. Replace f(x) with y
2. Interchange x and y
3. Solve for y
Domain: x > ­1
Range: all NonNegative Numbers
Nov 13­8:21 AM
Composition of Inverse Functions
If f and f ­1 are inverse functions, then...
f (f ­1(x)) = x
and
f ­1(f(x)) = x
f(x) = 5x + 11
f ­1(x) = ???
Nov 13­8:32 AM
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A27­7Notes.notebook
March 29, 2016
Composition Example:
Find f ­1(f (777))
Find f (f ­1(­5802))
Nov 18­8:15 AM
HW #43
7­7 P410 #1,5,6,8,9,11,12,23,31,32
Please put your name and class period at the top of
the homework. Also include the homework number.
Aug 19­6:25 AM
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