1. Questions over 4.6 HW???

2. 4.7 (Green) Solve Exponential and Logarithmic Equations No School: Monday Logarithms Test: 1/21/10 (Thursday)

3. Vocabulary: Exponential equations are equations in which variable expressions occur as exponents. Logarithmic equations are equations that involve logarithms of variable expressions.

4. Vocabulary: Property of Equality for Exponential Equations:  If b is a positive number other than 1, then b x = b y if and only if x = y. Property of Equality for Logarithmic Equations:  If b, x, and y are positive numbers with b = 1, then log b x = log b y if and only if x = y.

5. Example 1: Solve 8 x = 4 x + 1

6. You Try: Solve 5 3x + 1 = 25 x + 1

7. Example 2: Solve 8 x = 23

8. You Try: Solve 4 3x = 9

9. Example 3: Solve log 8 (x + 6) = log 8 (4 – x)

10. You Try: Solve 1. log 7 (x + 2) = log 7 (2 – 3x) 2. ln(4 – 5x) = ln(x + 10)

11. Example 4: Find the solution(s) of log x + log(x + 3) = 1 You need to check for extraneous solutions….fakers!

12. You Try: Solve 1. log 6 x + log 6 (x – 5) = 2 2. 2 ln x = ln(2x – 3) + ln(x – 2)

13. Homework: Pg. 161 #1-41odd You need to practice! Your FIRST test (55% of your grade) is next THURSDAY!!!!