Exponential Growth and Decay

What is the Domain of this exponential function?

• y=1

• x=0

• All Real Numbers

• x>0

What is the Range of this function?

• y> 0

• x> 0

• All Real Numbers

• y= 1

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

Classify the model as Exponential GROWTH or DECAY.
A=1200(.85)⁶

• Growth
• Decay

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

• 300
• 1.16
• .16
• x

Suppose a culture of bacteria begins with 5000 cells and dies by 30% each year. Write an equation that represents this situation.

• y=5000(0.7)^x
• y=30(5000)^x
• y=5000(1.3)^x
• y=5000x^x

Classify the model as Exponential GROWTH or DECAY.

f(x) = 10(1.01)^x

• Growth

• Decay

A bank account earning annual compound interest was opened, and no additional withdraws or deposits were made after the initial deposit. The balance in the account after x years can be modeled by b(x)=850(1.025)^x.

Which statement is the best interpretation of one of the values in this function?

• The initial balance in the account decreases at a rate of 97.5% each year.

• The balance in the account increases at a rate of 2.5% each year.

• The initial balance of the account was $1,025.

• The balance in the account at the end of one year is $850.