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Practice

5.9.6 Practice

5.9.6 • Practice

Complete the following questions to practice the skills you have learned in this lesson.

  1. The number of people with the flu during an epidemic is a function, f , of the number of days, d , since the epidemic began. The equation f ( d ) = 50 ⋅ ( 3 2 ) d defines f .
  1. How many people had the flu at the beginning of the epidemic?
    1. What does f ( 1 ) mean in this situation?
  1. The number of people infected after 1 year.
  2. The number of people infected grows by a factor of 1.
  3. The number of people infected 1 day after the epidemic began.
  4. There was 1 year of the epidemic.
  1. The function, f , gives the dollar value of a bond t  years after the bond was purchased. The graph of f  is shown.

    Graph of function.

    1. What is f ( 0 ) ?
    1. When is f ( t ) = 1500 ? Estimate to the nearest whole number.
  1. A function f gives the number of stray cats in a town t years since the town started an animal control program. The program includes both sterilizing stray cats and finding homes to adopt them. An equation representing f is f ( t ) = 243 ( 1 3 ) t .

    1. What is the value of f ( t ) when t is 0?
    1. What is the value of f ( t ) when t is 1?
  1. Function g gives the amount of a chemical in a person’s body, in milligrams, t hours since the patient took the drug. The equation g ( t ) = 600 ⋅ ( 3 5 ) t defines this function.

    1. Which is the best choice for the domain of g ?
  1. 0 ≤ t ≤ 600
  2. t ≤ 600
  3. t ≥ 600
  4. t ≥ 0
    1. Which is the best choice for the range of g ?
  1. 0 < g ≤ 600
  2. g ≤ 600
  3. g ≥ 600
  4. g > 0