Exponential Functions, Half-Life and Compound Interest

In the exponential function f(x) = b^x , b is called as the _______.

• base

• dependent variable

• exponent

• independent variable

Which of the following defines an exponential function?

• f(x) = 2x²

• f(x) = 2x - 1

• f(x) = 3^x

• f(x) = x² + 1

Solve for f(x) = 2^x+1, if x = 2

• 2

• 4

• 8

• 16

Which of the given situations illustrate an exponential change?

• A store has 100 regular customers and each month 5 new customers come

• The number of organisms in a culture doubles every 5 hours

• The monthly wage of a laborer increase by 75 every year

• As x increases the value of y increases

What do you call a quantity that decreases at a rate proportional to its current value?

• Population Growth

• Exponential Growth

• Exponential Decay

• Compound Interest

Which of the following situations describe an exponential decay?

• The number of rabbits doubles every month

• The population decreases every year by 100

• The atmospheric pressure decreases as you go higher

• The amount of money increases every year

What is the approximate value of e in the equation y = e^x ?

• 3.1416

• 31.416

• 2.71828

• 27.1828

Half-life is the time required for a quantity to reduce to half its initial value. Which of the following represents exponential function involving half-life?

What if the 200 bacteria in a certain culture doubles every 3 hours? What is the exponential model for the given situation?

What if the 200 bacteria in a certain culture doubles every 3 hours? How many bacteria are there after 9 hours?

• 1600

• 1800

• 2000

• 2100