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- 1.
- Suppose that
*b*satisfies*b*> 1. Explain the relationship between the graphs of*f*(*x*) =*b*^{x} - 2.
- Suppose that
*f*(*x*) is an exponential function that satisfies . Find the value of*b*so that*f*(*x*) =*b*^{x}*f*(3). - 3.
- Suppose that the population of a certain bacteria can be modeled
by an exponential function. In a particular experiment, the number of
bacteria was 50,000 at
*t*=0. Four hours later, the number of bacteria was 150,000. Suppose a second experiment is performed under the same conditions, but the number of bacteria at*t*=0 is only 20,000. Show, using the equation for exponential growth, that the predicted number of bacteria after four hours in this second experiment is 60,000. - 4.
- Suppose that for a certain drug, the following results were
obtained. Immediately after the drug was administered, the
concentration was 4.8 mg/ml. Three hours later, the concentration had
dropped to 2.23 mg/ml. Determine the value of
*k*for this drug. - 5.
- Suppose that for the drug in the previous exercise, the maximum safe level is and the minimum effective level is . What is the maximum possible time between doses for this drug?

1/23/1998