Exponential Functions Key Features

Write an equations that models the data shown.

Suppose the population of a species of insects doubles every year. The function gives the number of insects after x years. How many insects will there be after 3 years?

• 9600

• 12,800

• 200

• 8000

What type of function is
y = 7(5/4)^x?

• Exponential Growth

• Exponential Decay

• Linear

• None of the above

Determine the asymptote for the function
f(x)=3(2)^x-4+5

• x=4

• y=4

• x=5

• y=5

Determine the range for the function
f(x)=3(2)^x-4+5

• [5,∞)

• (5,∞)

• [4,∞)

• (4,∞)

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

• f(x)=400(.97)^x

• f(x)=400(1-0.03)^x

• f(x)=400(1.03)^x

• f(x)=400(0.03)^x

A new savings account is opened with $1500 and gains 1.5% annual interest. What is the exponential function?

• f(x)=1500(1+1.5)^x

• f(x)=1500(1+0.015)^x

• f(x)=1500(1.00375)^x

• f(x)=1500(1.5)^x

Write an equation that models the following situation:
Samantha's hair was known to grow very rapidly. It began at a length of 6 in and grew at a rate of 14% a week.

• y=6(0.14)^x

• y=6(1+14)^x

• y=6(1.14)^x

• y=6(0.86)^x

The value of a car is $15,000 and depreciates at a rate of 8% per year. What is the exponential equation?

• y=8(15,000)^x

• y=15,000(1.08)^x

• y=15,000(0.92)^x

• y=15,000(0.08)^x

What is a, the initial amount, for the function: f(x) = 300(1.16)^x?

• 300

• 1.16

• .16

• x