Key Features of Exponential Functions Review

What is the domain of the function shown?

• All real numbers

• All real numbers greater than 1

What is the domain of the function shown below?

• -2 < x < 5

• 0 < x < 12

• y > 0

• All Real Numbers

Is the function below increasing or decreasing? f(x)=2(4)^x.

• Increasing

• Decreasing

Which equation best represents the graph above?

• f(x)=5(.5)^x

• f(x)=10(.25)^x

• f(x)=10(5)^x

• f(x)=10(.75)^x

Which of the following statement about the graph of y=6(.5)^x is TRUE?

• The equation of the asymptote is x=0.

• The y-intercept is at 6

• The graph is increasing

• The graph will never cross the y axis

Which of the following statements is true about the graph of the equation above?

• The equation of the asymptote is y=0.

• The function is increasing

• The initial value is 3/4

• The constant ratio is 1/4

Look at the graph and answer each question.

Is the graph increasing or decreasing?

What is the y-intercept?

What is the asymptote?

• Increasing

  y-intercept: (0, 5)

  asymptote: y = 0

• Decreasing

  y-intercept: (0, 5)

  asymptote: y = 0

• Increasing

  y-intercept: (0, 5)

  asymptote: y = 5

• Decreasing

  y-intercept: (5, 0)

  asymptote: x = 0

The value of some cell phones changes exponentially after initial release. Here are graphs showing the depreciation of two phones 1, 2, and 3 years after they were released.

What does the point (2, 360) of Phone A represent in this situation?

• Phone A is worth $2 after 360 years

• Phone A is worth $360 after 2 years

• Phone A has an initial amount of $360

• Phone A will be completely depreciated in value after 2 years.

The value of some cell phones changes exponentially after initial release. Here are graphs showing the depreciation of two phones 1, 2, and 3 years after they were released.

What is an appropriate domain for both functions?