Exponential Functions Mixed Practice

Identify the y-intercept (initial value) in the function f(x)=13(.27)^x

• (.27)^x
• .27
• 13
• 3.51

Is the following function and example of decay or growth?

f(x)=2(0.85)^x

• Exponential Decay

• Exponential Growth

Which of the following represents an exponential growth function whose y-intercept is 50?

• y = 50(.05)^x
• y = 50x - 4
• y = (2)^x + 50
• y = 50(1.4)^x

Is the following function an example of decay or growth?

f(x) = 2(1.25)^x

• Exponential Growth

• Exponential Decay

What is the x-intercept of the exponential function graphed? 

• (0 , 1)

• (0 , -2)

• There are no x-intercepts due to the horizontal asymptote at y = 0

• x < -2

The expression f(t) = 12(1.015)^t models the population of elephants in a wildlife refuge after t years since 1975. Is the population of elephants increasing or decreasing?

• Increasing
• Decreasing

A new savings account is opened with $400 and gains 3% every year. What is the exponential function?

• f(x)=400(1+3)^x
• f(x)=400(1-0.03)^x
• f(x)=400(1+0.03)^x
• f(x)=400(0.03)^x

What does the y-intercept of the graph represent?

• The amount of grams the material is gaining.
• The amount of grams the material is losing.
• The amount of grams remaining after so many years.
• The initial amount of grams.

The expression f(t) = 12(1.015)^t models the population of elephants in a wildlife refuge after t years since 1975. What does the value 12 represent?

• The predicted increase in number of elephants in the refuge each year.
• The predicted decrease in number of elephants in the refuge each year.
• The number of years it will take for the elephant population to stop increasing.
• The initial amount of elephants in the park.

What is the Domain of this exponential function?

• y = 1

• x = 0

• All Real Numbers

• x > 0