1. Warm up

2. Solution

3. Why do we care? Logarithms are functions that used to be very helpful, but most of their value has become obsolete now that we have fancy calculators. BUT! They still are extremely important in solving exponential equations. That is what we will use them for.

4. First we have to understand what a logarithm is before we can use it.

5. Definition of a Logarithm

6. Let’s use this definition to solve the warm-up.

7. What are all of these numbers?

8. Example 1

9. Solution

10. You try

11. Solution

12. One more, a little harder: Solve for x

13. Solution

14. We will also want to find exact values of logs. If the log is base 10, then it is easy to do on the calculator. If it is not base 10, we will have to put it in terms of base 10 to use the calculator.

15. Example

16. But, there is not a button if the base is not 10… We will use this rule to solve for exact values of logs on our calculators.

17. Example

19. Solution

20. You try

21. Answer

22. Homework 5.6 Worksheet 1:all, 2:a-e, 3:Skip, 4:skip, 5:a-g