1. L0garithmic Functions Chapter5Section2

2. Logarithmic Function  Recall in Section 4.3 we talked about inverse functions. Since the exponential function is one-to-one, it has an inverse function:

3. Definition of the Logarithmic Function Same bases Same exponents Logarithmic form Exponential form

4. Exponential vs. Logarithmic Form Logarithmic FormExponential Form log 2 x = y log 2 16 = y log 3 x = 2 10 2 =100 b 3 =64 a 0 = 1 a 1 = a Use the definition of a logarithm to fill in the missing form.

5. Example 2

6. Graphs of Logarithmic Functions

7. Common vs. Natural Logarithms  There are two bases used on your calculator. These are the common (base 10) and the natural (base e).

8. Richter Scale Example 3

9. Example 4

10. Logarithmic Properties