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7.1 EXPLORING EXPONENTIAL
MODELS

      Chapter 7: Exponential and Logarithmic
      Functions
Exponential Functions
   The general form of an exponential function is
    where x is a real number, a  0, b > 0, and b 
    1.
   To graph an Exponential Function: create a
    table of values and plot the points
     Example:   Graph
Exponential Functions
   Exponential Functions always have the curved
    shape
   They also have an asymptote, a line that the
    graph approaches but never touches or
    crosses              The domain is all real
                         numbers.

                         The range is y > 0
Exponential Functions
    There are two types of exponential behavior

Exponential                   Exponential Decay
 Growth                          As the value of x
   As the value of x             increases, the value
    increases, the value          of y decreases
    of y increases
Exponential Functions
   For the function
     If a > 0 and b >1, the function represents
      exponential growth
     If a > 0 and 0 < b < 1, the function represents
      exponential decay

     The y-intercept of the graph is at (0, a)
     The asymptote is y = 0
Without graphing, determine whether the function
represents exponential growth or decay. Then find
the y-intercept.
Exponential Growth and Decay
   In the function         , b represents the growth
    or decay factor.
     If b > , then it is the growth factor
     If 0 < b < 1, then it is the decay factor
Exponential Growth and Decay
   To model exponential growth and decay we use
    the following function           To use this
                                         function:
                                         1. Identify the
                                            value of the
                                            variables
                                         2. Plug the known
                                            values into the
                                            equation
                                         3. Solve for the
     For growth or decay to be exponential,unknown value
                                             a quantity
     changes by a fixed percentage each time period
Example: Page 436
   You invested $1000 in a savings account at
    the end of the 6th grade. The account pays 5%
    annual interest. How much money will be in
    the account after 6 years?
Homework
   P. 439 #1  6 all, 8, 10  25 odd, 26 (parts a &
    b), 27, 28

More Related Content

7.1

  • 1. 7.1 EXPLORING EXPONENTIAL MODELS Chapter 7: Exponential and Logarithmic Functions
  • 2. Exponential Functions The general form of an exponential function is where x is a real number, a 0, b > 0, and b 1. To graph an Exponential Function: create a table of values and plot the points Example: Graph
  • 3. Exponential Functions Exponential Functions always have the curved shape They also have an asymptote, a line that the graph approaches but never touches or crosses The domain is all real numbers. The range is y > 0
  • 4. Exponential Functions There are two types of exponential behavior Exponential Exponential Decay Growth As the value of x As the value of x increases, the value increases, the value of y decreases of y increases
  • 5. Exponential Functions For the function If a > 0 and b >1, the function represents exponential growth If a > 0 and 0 < b < 1, the function represents exponential decay The y-intercept of the graph is at (0, a) The asymptote is y = 0
  • 6. Without graphing, determine whether the function represents exponential growth or decay. Then find the y-intercept.
  • 7. Exponential Growth and Decay In the function , b represents the growth or decay factor. If b > , then it is the growth factor If 0 < b < 1, then it is the decay factor
  • 8. Exponential Growth and Decay To model exponential growth and decay we use the following function To use this function: 1. Identify the value of the variables 2. Plug the known values into the equation 3. Solve for the For growth or decay to be exponential,unknown value a quantity changes by a fixed percentage each time period
  • 9. Example: Page 436 You invested $1000 in a savings account at the end of the 6th grade. The account pays 5% annual interest. How much money will be in the account after 6 years?
  • 10. Homework P. 439 #1 6 all, 8, 10 25 odd, 26 (parts a & b), 27, 28