College Algebra Chapter 4 Exponential and Logarithmic Functions Section 4.1 Inverse Functions
1. Identify One-to-One Functions 2. Determine Whether Two Functions Are Inverses 3. Find the Inverse of a Function
Identify One-to-One Functions A function f is a one-to-one function if for a and b in the domain of f, or equivalently,
Example 1: Determine if the relation defines y as a one-to-one function of x.
Example 2: Determine if the relation defines y as a one-to-one function of x.
Identify One-to-One Functions A function y = f (x) is a one-to-one function if no horizontal line intersects the graph in more than one place.
Example 3: Determine if the relation defines y as a one-to-one function of x.
Example 4: Determine if the relation defines y as a one-to-one function of x.
Example 5: Determine if the relation defines y as a one-to-one function of x.
Example 6: Use the definition of a one-to-one function to determine whether the function is one-to-one. (Show that if )
Example 7: Use the definition of a one-to-one function to determine whether the function is one-to-one. (Show that if )
1. Identify One-to-One Functions 2. Determine Whether Two Functions Are Inverses 3. Find the Inverse of a Function
Determine Whether Two Functions Are Inverses Inverse Functions: Let f be a one-to-one function. Then g is the inverse of f if the following conditions are both true. Given a function and its inverse , then the definition implies that
Example 8: Determine whether the two functions are inverses.
Example 9: Determine whether the two functions are inverses.
1. Identify One-to-One Functions 2. Determine Whether Two Functions Are Inverses 3. Find the Inverse of a Function
Find the Inverse of a Function Procedure to Find an Equation of an Inverse of a Function For a one-to-one function defined by y = f (x), the equation of the inverse can be found as follows: Step 1 Replace f (x) by y. Step 2 Interchange x and y. Step 3 Solve for y. Step 4 Replace y by .
Example 10: A one-to-one function is given. Write an equation for the inverse function.
Example 10 continued:
Example 11: A one-to-one function is given. Write an equation for the inverse function.
Example 11 continued:
Example 11 continued:
Example 11 continued:
Example 11 continued:
Example 12: A one-to-one function is given. Write an equation for the inverse function.
Example 12 continued:
Example 13: The graph of a function is given. Graph the inverse function.