Section 5-3
Inverse Functions and Relations
Essential Questions
• How do you find the inverse of a function or
relation?

• How do you determine whether two functions
or relations are inverses?
Vocabulary
1. Inverse Relation:
2. Inverse Function:
Vocabulary
1. Inverse Relation: When the coordinates of a
relation are switched
2. Inverse Function:
Vocabulary
1. Inverse Relation: When the coordinates of a
relation are switched
Two relations are inverse relations IFF one
relation contains (a, b) and the other relation
contains (b, a).
2. Inverse Function:
Vocabulary
1. Inverse Relation: When the coordinates of a
relation are switched
Two relations are inverse relations IFF one
relation contains (a, b) and the other relation
contains (b, a).
2. Inverse Function: When the domain and range
of one function are switched to form a new
function
Vocabulary
1. Inverse Relation: When the coordinates of a
relation are switched
Two relations are inverse relations IFF one
relation contains (a, b) and the other relation
contains (b, a).
2. Inverse Function: When the domain and range
of one function are switched to form a new
function
If f and f-1 are inverses, then f(a) = b IFF 

f-1(b) = a
Vocabulary
3. Horizontal Line Test:
Vocabulary
3. Horizontal Line Test: Will test if the inverse of a
function is also a function
Vocabulary
3. Horizontal Line Test: Will test if the inverse of a
function is also a function
A function f has an inverse function f-1 IFF
each horizontal line intersects the graph of
the function in at most one point
Example 1
{(1,3),(6,3),(6,0),(1,0)}
The ordered pairs of the relation

are the coordinates of the vertices of a
rectangle. Find the inverse of this relation.
Describe the graph of the inverse.
Example 1
{(1,3),(6,3),(6,0),(1,0)}
The ordered pairs of the relation

are the coordinates of the vertices of a
rectangle. Find the inverse of this relation.
Describe the graph of the inverse.
{(3,1),(3,6),(0,6),(0,1)}
Example 1
{(1,3),(6,3),(6,0),(1,0)}
The ordered pairs of the relation

are the coordinates of the vertices of a
rectangle. Find the inverse of this relation.
Describe the graph of the inverse.
{(3,1),(3,6),(0,6),(0,1)}
The points in the inverse are still the vertices of a
rectangle, but reflected across the line y = x.
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 2
Find the inverse of the function below. Graph
the original function and its inverse.
f (x ) = −
1
2
x +1
y = −
1
2
x +1
x = −
1
2
y +1
x −1= −
1
2
y
−2x + 2 = y
f −1
(x ) = −2x + 2 x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
y = x 2
− 4x +1
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
y = x 2
− 4x +1
x = y 2
− 4y +1
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
y = x 2
− 4x +1
x = y 2
− 4y +1
x −1= y 2
− 4y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
y = x 2
− 4x +1
x = y 2
− 4y +1
x −1= y 2
− 4y
1
2
i −4
⎛
⎝⎜
⎞
⎠⎟
2
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
y = x 2
− 4x +1
x = y 2
− 4y +1
x −1= y 2
− 4y
1
2
i −4
⎛
⎝⎜
⎞
⎠⎟
2
−2( )2
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
y = x 2
− 4x +1
x = y 2
− 4y +1
x −1= y 2
− 4y
1
2
i −4
⎛
⎝⎜
⎞
⎠⎟
2
−2( )2
4
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
y = x 2
− 4x +1
x = y 2
− 4y +1
x −1= y 2
− 4y
1
2
i −4
⎛
⎝⎜
⎞
⎠⎟
2
−2( )2
4
x −1+ 4 = y 2
− 4y + 4
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
y = x 2
− 4x +1
x = y 2
− 4y +1
x −1= y 2
− 4y
1
2
i −4
⎛
⎝⎜
⎞
⎠⎟
2
−2( )2
4
x −1+ 4 = y 2
− 4y + 4
x + 3 = y 2
− 4y + 4
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
y = x 2
− 4x +1
x = y 2
− 4y +1
x −1= y 2
− 4y
1
2
i −4
⎛
⎝⎜
⎞
⎠⎟
2
−2( )2
4
x −1+ 4 = y 2
− 4y + 4
x + 3 = y 2
− 4y + 4
x + 3 = (y − 2)2
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
y = x 2
− 4x +1
x = y 2
− 4y +1
x −1= y 2
− 4y
1
2
i −4
⎛
⎝⎜
⎞
⎠⎟
2
−2( )2
4
x −1+ 4 = y 2
− 4y + 4
x + 3 = y 2
− 4y + 4
x + 3 = (y − 2)2
± x + 3 = (y − 2)2
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
y = x 2
− 4x +1
x = y 2
− 4y +1
x −1= y 2
− 4y
1
2
i −4
⎛
⎝⎜
⎞
⎠⎟
2
−2( )2
4
x −1+ 4 = y 2
− 4y + 4
x + 3 = y 2
− 4y + 4
x + 3 = (y − 2)2
± x + 3 = (y − 2)2
± x + 3 = y − 2
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
y = x 2
− 4x +1
x = y 2
− 4y +1
x −1= y 2
− 4y
1
2
i −4
⎛
⎝⎜
⎞
⎠⎟
2
−2( )2
4
x −1+ 4 = y 2
− 4y + 4
x + 3 = y 2
− 4y + 4
x + 3 = (y − 2)2
± x + 3 = (y − 2)2
± x + 3 = y − 2
2 ± x + 3 = y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
y = x 2
− 4x +1
x = y 2
− 4y +1
x −1= y 2
− 4y
1
2
i −4
⎛
⎝⎜
⎞
⎠⎟
2
−2( )2
4
x −1+ 4 = y 2
− 4y + 4
x + 3 = y 2
− 4y + 4
x + 3 = (y − 2)2
± x + 3 = (y − 2)2
± x + 3 = y − 2
2 ± x + 3 = y
f −1
= 2 ± x + 3
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 3
Find the inverse of the function below. Then
graph the function and its inverse. If necessary,
restrict the domain of the inverse so that it is a
function.
f (x ) = x 2
− 4x +1
f −1
= 2 ± x + 3
x =
−b
2a
x =
4
2
x = 2
f −1
= 2 + x + 3; (−∞,2]
f −1
= 2 − x + 3; [2,+∞)
x
y
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
Two functions f and g are inverse functions IFF both
of their compositions are the identity function.
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
Two functions f and g are inverse functions IFF both
of their compositions are the identity function.
f(x) and g(x) are inverses IFF
[f !g](x ) = x and [g !f ](x ) = x
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
Two functions f and g are inverse functions IFF both
of their compositions are the identity function.
f(x) and g(x) are inverses IFF
[f !g](x ) = x and [g !f ](x ) = x
f (x ) =
3
4
x − 6
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
Two functions f and g are inverse functions IFF both
of their compositions are the identity function.
f(x) and g(x) are inverses IFF
[f !g](x ) = x and [g !f ](x ) = x
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
[f ! g](x )
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
[f ! g](x )
= f [g(x )]
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
[f ! g](x )
= f [g(x )]
= f
4
3
x + 8
⎛
⎝⎜
⎞
⎠⎟
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
[f ! g](x )
= f [g(x )]
= f
4
3
x + 8
⎛
⎝⎜
⎞
⎠⎟
=
3
4
4
3
x + 8
⎛
⎝⎜
⎞
⎠⎟ − 6
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
[f ! g](x )
= f [g(x )]
= f
4
3
x + 8
⎛
⎝⎜
⎞
⎠⎟
=
3
4
4
3
x + 8
⎛
⎝⎜
⎞
⎠⎟ − 6
= x + 6 − 6
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
[f ! g](x )
= f [g(x )]
= f
4
3
x + 8
⎛
⎝⎜
⎞
⎠⎟
=
3
4
4
3
x + 8
⎛
⎝⎜
⎞
⎠⎟ − 6
= x + 6 − 6
= x
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
[f ! g](x )
= f [g(x )]
= f
4
3
x + 8
⎛
⎝⎜
⎞
⎠⎟
=
3
4
4
3
x + 8
⎛
⎝⎜
⎞
⎠⎟ − 6
= x + 6 − 6
= x
[f ! g](x ) = x
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
[g !f ](x )
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
[g !f ](x )
= g[f (x )]
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
[g !f ](x )
= g[f (x )]
= g
3
4
x − 6
⎛
⎝⎜
⎞
⎠⎟
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
[g !f ](x )
= g[f (x )]
= g
3
4
x − 6
⎛
⎝⎜
⎞
⎠⎟
=
4
3
3
4
x − 6
⎛
⎝⎜
⎞
⎠⎟ + 8
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
[g !f ](x )
= g[f (x )]
= g
3
4
x − 6
⎛
⎝⎜
⎞
⎠⎟
=
4
3
3
4
x − 6
⎛
⎝⎜
⎞
⎠⎟ + 8
= x − 8 + 8
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
[g !f ](x )
= g[f (x )]
= g
3
4
x − 6
⎛
⎝⎜
⎞
⎠⎟
=
4
3
3
4
x − 6
⎛
⎝⎜
⎞
⎠⎟ + 8
= x − 8 + 8
= x
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
[g !f ](x )
= g[f (x )]
= g
3
4
x − 6
⎛
⎝⎜
⎞
⎠⎟
=
4
3
3
4
x − 6
⎛
⎝⎜
⎞
⎠⎟ + 8
= x − 8 + 8
= x
[g !f ](x ) = x
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
Example 4
Determine whether the functions below are inverse
functions. Explain your reasoning.
f (x ) =
3
4
x − 6 g(x ) =
4
3
x + 8
Since and , these functions
are inverses.
[f !g](x ) = x [g !f ](x ) = x

Algebra 2 Section 5-3

  • 1.
  • 2.
    Essential Questions • Howdo you find the inverse of a function or relation? • How do you determine whether two functions or relations are inverses?
  • 3.
  • 4.
    Vocabulary 1. Inverse Relation:When the coordinates of a relation are switched 2. Inverse Function:
  • 5.
    Vocabulary 1. Inverse Relation:When the coordinates of a relation are switched Two relations are inverse relations IFF one relation contains (a, b) and the other relation contains (b, a). 2. Inverse Function:
  • 6.
    Vocabulary 1. Inverse Relation:When the coordinates of a relation are switched Two relations are inverse relations IFF one relation contains (a, b) and the other relation contains (b, a). 2. Inverse Function: When the domain and range of one function are switched to form a new function
  • 7.
    Vocabulary 1. Inverse Relation:When the coordinates of a relation are switched Two relations are inverse relations IFF one relation contains (a, b) and the other relation contains (b, a). 2. Inverse Function: When the domain and range of one function are switched to form a new function If f and f-1 are inverses, then f(a) = b IFF f-1(b) = a
  • 8.
  • 9.
    Vocabulary 3. Horizontal LineTest: Will test if the inverse of a function is also a function
  • 10.
    Vocabulary 3. Horizontal LineTest: Will test if the inverse of a function is also a function A function f has an inverse function f-1 IFF each horizontal line intersects the graph of the function in at most one point
  • 11.
    Example 1 {(1,3),(6,3),(6,0),(1,0)} The orderedpairs of the relation are the coordinates of the vertices of a rectangle. Find the inverse of this relation. Describe the graph of the inverse.
  • 12.
    Example 1 {(1,3),(6,3),(6,0),(1,0)} The orderedpairs of the relation are the coordinates of the vertices of a rectangle. Find the inverse of this relation. Describe the graph of the inverse. {(3,1),(3,6),(0,6),(0,1)}
  • 13.
    Example 1 {(1,3),(6,3),(6,0),(1,0)} The orderedpairs of the relation are the coordinates of the vertices of a rectangle. Find the inverse of this relation. Describe the graph of the inverse. {(3,1),(3,6),(0,6),(0,1)} The points in the inverse are still the vertices of a rectangle, but reflected across the line y = x.
  • 14.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 x y
  • 15.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x y
  • 16.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x y
  • 17.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y x y
  • 18.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y x y
  • 19.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 20.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 21.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 22.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 23.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 24.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 25.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 26.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 27.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 28.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 29.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 30.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 31.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 32.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 33.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 34.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 35.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 36.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 37.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 38.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 39.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 40.
    Example 2 Find theinverse of the function below. Graph the original function and its inverse. f (x ) = − 1 2 x +1 y = − 1 2 x +1 x = − 1 2 y +1 x −1= − 1 2 y −2x + 2 = y f −1 (x ) = −2x + 2 x y
  • 41.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1
  • 42.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 y = x 2 − 4x +1
  • 43.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 y = x 2 − 4x +1 x = y 2 − 4y +1
  • 44.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 y = x 2 − 4x +1 x = y 2 − 4y +1 x −1= y 2 − 4y
  • 45.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 y = x 2 − 4x +1 x = y 2 − 4y +1 x −1= y 2 − 4y 1 2 i −4 ⎛ ⎝⎜ ⎞ ⎠⎟ 2
  • 46.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 y = x 2 − 4x +1 x = y 2 − 4y +1 x −1= y 2 − 4y 1 2 i −4 ⎛ ⎝⎜ ⎞ ⎠⎟ 2 −2( )2
  • 47.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 y = x 2 − 4x +1 x = y 2 − 4y +1 x −1= y 2 − 4y 1 2 i −4 ⎛ ⎝⎜ ⎞ ⎠⎟ 2 −2( )2 4
  • 48.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 y = x 2 − 4x +1 x = y 2 − 4y +1 x −1= y 2 − 4y 1 2 i −4 ⎛ ⎝⎜ ⎞ ⎠⎟ 2 −2( )2 4 x −1+ 4 = y 2 − 4y + 4
  • 49.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 y = x 2 − 4x +1 x = y 2 − 4y +1 x −1= y 2 − 4y 1 2 i −4 ⎛ ⎝⎜ ⎞ ⎠⎟ 2 −2( )2 4 x −1+ 4 = y 2 − 4y + 4 x + 3 = y 2 − 4y + 4
  • 50.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 y = x 2 − 4x +1 x = y 2 − 4y +1 x −1= y 2 − 4y 1 2 i −4 ⎛ ⎝⎜ ⎞ ⎠⎟ 2 −2( )2 4 x −1+ 4 = y 2 − 4y + 4 x + 3 = y 2 − 4y + 4 x + 3 = (y − 2)2
  • 51.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 y = x 2 − 4x +1 x = y 2 − 4y +1 x −1= y 2 − 4y 1 2 i −4 ⎛ ⎝⎜ ⎞ ⎠⎟ 2 −2( )2 4 x −1+ 4 = y 2 − 4y + 4 x + 3 = y 2 − 4y + 4 x + 3 = (y − 2)2 ± x + 3 = (y − 2)2
  • 52.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 y = x 2 − 4x +1 x = y 2 − 4y +1 x −1= y 2 − 4y 1 2 i −4 ⎛ ⎝⎜ ⎞ ⎠⎟ 2 −2( )2 4 x −1+ 4 = y 2 − 4y + 4 x + 3 = y 2 − 4y + 4 x + 3 = (y − 2)2 ± x + 3 = (y − 2)2 ± x + 3 = y − 2
  • 53.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 y = x 2 − 4x +1 x = y 2 − 4y +1 x −1= y 2 − 4y 1 2 i −4 ⎛ ⎝⎜ ⎞ ⎠⎟ 2 −2( )2 4 x −1+ 4 = y 2 − 4y + 4 x + 3 = y 2 − 4y + 4 x + 3 = (y − 2)2 ± x + 3 = (y − 2)2 ± x + 3 = y − 2 2 ± x + 3 = y
  • 54.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 y = x 2 − 4x +1 x = y 2 − 4y +1 x −1= y 2 − 4y 1 2 i −4 ⎛ ⎝⎜ ⎞ ⎠⎟ 2 −2( )2 4 x −1+ 4 = y 2 − 4y + 4 x + 3 = y 2 − 4y + 4 x + 3 = (y − 2)2 ± x + 3 = (y − 2)2 ± x + 3 = y − 2 2 ± x + 3 = y f −1 = 2 ± x + 3
  • 55.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x y
  • 56.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x y
  • 57.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x y
  • 58.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 x y
  • 59.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] x y
  • 60.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 61.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 62.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 63.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 64.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 65.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 66.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 67.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 68.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 69.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 70.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 71.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 72.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 73.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 74.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 75.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 76.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 77.
    Example 3 Find theinverse of the function below. Then graph the function and its inverse. If necessary, restrict the domain of the inverse so that it is a function. f (x ) = x 2 − 4x +1 f −1 = 2 ± x + 3 x = −b 2a x = 4 2 x = 2 f −1 = 2 + x + 3; (−∞,2] f −1 = 2 − x + 3; [2,+∞) x y
  • 78.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning.
  • 79.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. Two functions f and g are inverse functions IFF both of their compositions are the identity function.
  • 80.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. Two functions f and g are inverse functions IFF both of their compositions are the identity function. f(x) and g(x) are inverses IFF [f !g](x ) = x and [g !f ](x ) = x
  • 81.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. Two functions f and g are inverse functions IFF both of their compositions are the identity function. f(x) and g(x) are inverses IFF [f !g](x ) = x and [g !f ](x ) = x f (x ) = 3 4 x − 6
  • 82.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. Two functions f and g are inverse functions IFF both of their compositions are the identity function. f(x) and g(x) are inverses IFF [f !g](x ) = x and [g !f ](x ) = x f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8
  • 83.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8
  • 84.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 [f ! g](x )
  • 85.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 [f ! g](x ) = f [g(x )]
  • 86.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 [f ! g](x ) = f [g(x )] = f 4 3 x + 8 ⎛ ⎝⎜ ⎞ ⎠⎟
  • 87.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 [f ! g](x ) = f [g(x )] = f 4 3 x + 8 ⎛ ⎝⎜ ⎞ ⎠⎟ = 3 4 4 3 x + 8 ⎛ ⎝⎜ ⎞ ⎠⎟ − 6
  • 88.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 [f ! g](x ) = f [g(x )] = f 4 3 x + 8 ⎛ ⎝⎜ ⎞ ⎠⎟ = 3 4 4 3 x + 8 ⎛ ⎝⎜ ⎞ ⎠⎟ − 6 = x + 6 − 6
  • 89.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 [f ! g](x ) = f [g(x )] = f 4 3 x + 8 ⎛ ⎝⎜ ⎞ ⎠⎟ = 3 4 4 3 x + 8 ⎛ ⎝⎜ ⎞ ⎠⎟ − 6 = x + 6 − 6 = x
  • 90.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 [f ! g](x ) = f [g(x )] = f 4 3 x + 8 ⎛ ⎝⎜ ⎞ ⎠⎟ = 3 4 4 3 x + 8 ⎛ ⎝⎜ ⎞ ⎠⎟ − 6 = x + 6 − 6 = x [f ! g](x ) = x
  • 91.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8
  • 92.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 [g !f ](x )
  • 93.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 [g !f ](x ) = g[f (x )]
  • 94.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 [g !f ](x ) = g[f (x )] = g 3 4 x − 6 ⎛ ⎝⎜ ⎞ ⎠⎟
  • 95.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 [g !f ](x ) = g[f (x )] = g 3 4 x − 6 ⎛ ⎝⎜ ⎞ ⎠⎟ = 4 3 3 4 x − 6 ⎛ ⎝⎜ ⎞ ⎠⎟ + 8
  • 96.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 [g !f ](x ) = g[f (x )] = g 3 4 x − 6 ⎛ ⎝⎜ ⎞ ⎠⎟ = 4 3 3 4 x − 6 ⎛ ⎝⎜ ⎞ ⎠⎟ + 8 = x − 8 + 8
  • 97.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 [g !f ](x ) = g[f (x )] = g 3 4 x − 6 ⎛ ⎝⎜ ⎞ ⎠⎟ = 4 3 3 4 x − 6 ⎛ ⎝⎜ ⎞ ⎠⎟ + 8 = x − 8 + 8 = x
  • 98.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 [g !f ](x ) = g[f (x )] = g 3 4 x − 6 ⎛ ⎝⎜ ⎞ ⎠⎟ = 4 3 3 4 x − 6 ⎛ ⎝⎜ ⎞ ⎠⎟ + 8 = x − 8 + 8 = x [g !f ](x ) = x
  • 99.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8
  • 100.
    Example 4 Determine whetherthe functions below are inverse functions. Explain your reasoning. f (x ) = 3 4 x − 6 g(x ) = 4 3 x + 8 Since and , these functions are inverses. [f !g](x ) = x [g !f ](x ) = x