1. Warm-up 1.Find f(12). 2.f(x)=140. Find x.

2. Answer 1.f(12) = 1 2. f(9) = 140

3. Inverses of Functions

4. Definition of an Inverse You get the inverse of a relation by switching the x and y coordinates of all the points, OR by exchanging the x and y variables in an equation.

5. Function or not a function? It is important to know that inverses of functions are not always functions themselves. Sometimes it is difficult to tell just by looking at the equation. Graph the inverse on your calculator, and do the “vertical line test” to check if it is a function.

6. Notation

7. Example 1

8. Steps in finding the inverse equation 1.Switch the dependent and independent variables (usually x and y) 2.Then, solve for the new dependent variable. 3.Write final answer in function notation.

9. Example 2

10. Solution part 1

11. Solution continued

12. Example 3: You try

13. Answer

14. Homework 5.5 Worksheet: Problems 2,3,4 Do problem 3 FIRST (in-class) so you can use a calculator to check if the inverse is a function.