Exponential Math Review

Which is an equation of the function graphed above?

• y = 4^–x

• y = 4^x

• y = 4^–x + 1

• y = 4^x + 1

Which function, when graphed, has the y-intercept that is farthest away from the origin?

• f(x) = 5(3.5)^x

• f(x) = 3^{(x + 1)}

• f(x) = ^–23(2)^{(x + 3)}

• f(x) = ^–11(5)^{(x + 2)}

Sara’s savings account balance can be modeled by the function f(x) = 850(1.005)^12x, where x is the number of years Sara has the money in the account. By about what percent is Sara’s savings account growing each year?

• 0.5%

• 0.6%

• 5.0%

• 6.0%

The population of a town after 1990 can be modeled by the expression I(1.045)^t where t represents the number of years since 1990 and I represents the population of the town in the year 1990. Which expression represents the monthly growth rate?

• I(1.045¹²)^12t

• I(1.045¹²)^1/12t

• I(1.045^1/12)^1/12t

• I(1.045^1/12)^12t

Genevieve deposited $400 into her bank account. The equation A(t) = 400(1.07)^t can be used to calculate the value of her money after t years. What is the annual interest rate she is earning on her deposit?

• 0.07%

• 1.07%

• 7%

• 107%

What type of function is f(x)=2(1/7)^x ?

• Exponential Growth

• Linear

• Exponential Decay

• None of the Abovee

Is the pictured graph growth, decay, or linear or none?  

• Exponential Growth

• Exponential Decay

• Linear

• None

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.

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

• y = 50(.05)^x

• y = 50x - 4

• y = (2)^x + 50

• y = 50(1.4)^x

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