1 MAC1105, College Algebra Study Questions for Common Final ...

29. Each of the following tables contains values representing either linear or exponential functions.
Find the equation for each function.
a.
x -2 -1 0 1 2
F(x) 1.12 2.8 7 17.5 43.75
b.
x -2 -1 0 1 2
G(x) 0.1 0.3 0.5 0.7 0.9
30. Write an equation for an exponential decay function where:
a. The initial population is 10,000 and the decay factor is
.
b. The initial population is 2.7 ∙ 10 and the decay factor is 0.27.
31. Plutonium -238 is used in bombs and power plants but is dangerously radioactive. It decays very
slowly into nonradioactive materials. If you started with 100 grams today, a year from now you
would have 99.2 grams.
a. Construct an exponential function to describe the decay of plutonium-238 over time.
b. How much of the original 100 grams of plutonium-238 would be left after 50 years?
After 500 years?
32. Below are graphs of four exponential functions. Match each function with its graph.
P = 5 ∙ 0.7 R = 10 ∙ 1.8 Q = 5 ∙ 0.4 S = 5 ∙ 3
33. Graph the functions f(x) = 30 + 5x and g(x) = 31.6 on the same grid. Supply the symbol < or >
in the blank that would make the statement true.
a. f(0) ________ g(0) e. f(-6) ________ g(-6)
b. f(6) ________ g (6) f. As x → + ∞, f(x) ________ g(x)
c. f(7) ________ g(7) g. As x → − ∞, f(x) ________ g(x)
d. f(-5) _______ g(-5)
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