1. Properties of Logarithms Section 8.5

2. WHAT YOU WILL LEARN: 1.How to use the properties of logarithms to simplify and evaluate expressions.

3. Some Questions How do you simplify the following:

4. So ….. Remember that logarithms are another way to write exponents. The Properties of Logarithms are based on the properties of exponents – Product Property: Quotient Property: Power Property:

5. Using Properties of Logarithms Use to approximate the following: 1. 2. log 5 21 3. log 5 49

6. You Try! Use to approximate the following: 1. 2. log 9 55 3. log 9 25

7. Expanding a Logarithmic Expression Expand. Assume x and y are positive.

8. You Try! Expand. Assume x and y are positive.

9. Condensing a Logarithmic Expressions Condense log 6 + 2 log 2 – log 3

10. You Try! Condense

11. Change of Base Formula and

12. Example Evaluate the expression log 3 7 using common and natural logarithms. 1. log 3 7 2. log 3 7

13. Homework page 496, 14-24 even, 30-42 even, 46-52 even, 58, 60, 70