Exponential Functions

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

Identify the y-intercept (initial value) of the function f(x)=2(4)^x.

• 2
• 4
• (2)^x
• 8

Does the graph represent an exponential growth or an exponential decay function?

• Exponential Growth
• Exponential Decay

The expression 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

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

• The number of elephants was 1,015 in 1975.
• The number of elephants increases by 1.5% each year.
• The number of elephants increases by 101.5% each year.
• The number of elephants is multiplied by 1.015 each year.

Is the graph exponential growth or decay?

• Exponential growth
• Exponential decay

Which represents exponential decay?

• A

• B

• C

• D