1. Exponential and Logarithmic Functions
Chapter 9
Exponential and Logarithmic Functions

2. Chapter Sections 9.1 – Composite and Inverse Functions
9.2 – Exponential Functions
9.3 – Logarithmic Functions
9.4 – Properties of Logarithms
9.5 – Common Logarithms
9.6 – Exponential and Logarithmic Equations
9.7 – Natural Exponential and Natural Logarithmic Functions
Chapter 1 Outline

3. Exponential and Logarithmic Equations
§ 9.6
Exponential and Logarithmic Equations

4. Solve Exponential and Logarithmic Equations
Properties for Solving Exponential and Logarithmic Equations
If x = y, then ax = ay.
If ax = ay, then x = y.
If x = y, then logbx = logby (x > 0, y > 0).
If logbx=logby, then x = y (x > 0, y > 0).

5. Solve Exponential and Logarithmic Equations
Example Solve the equation
Property 6b

6. Solve Exponential and Logarithmic Equations
Example Solve
Property 6d

7. Solve Applications
Example If there are initially 1000 bacteria in a culture, and the number of bacteria doubles each hour, the number of bacteria after t hours can be found by the formula
How long will it take for the culture to grow to 30,000 bacteria?
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8. Solve Applications
We want to find the value for t. To accomplish this we will use logarithms. Begin by taking the logarithm of both sides of the equation.
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9. Solve Applications
It will take about 4.91 hours for the culture to grow 30,000 bacteria.