Key Features of Exponential Functions
Growth or Decay 1
Growth or Decay 2
Compound Interest
Word Problems
100

What's the growth factor?

b=2

100

How do I know if an exponential function is exponential growth from an equation? 


The value of b is greater than 1
100

Does the graph represent exponential growth or decay?

Exponential Growth

100

You were charged 8.8% compounded semi annually on your loan of $860 for a 9 year term. What total did you pay to borrow the money after 9 years?

$1,866.84

100

Is the function exponential growth or decay?

Decay

200

If, y=a(bx ), What do a and b represent? 



a=initial amount/y-intercept

b=multiplier/growth factor

200

How do I know if an exponential function is exponential decay from an equation?

If the b is in between 0 and 1


200

A bunny population doubles every 6 months.  If the starting population is 10, how many will you have after 3 years?  What is the initial population?  What is the growth factor?


initial population = 10

growth rate = 2

200

Your mortgage of $30,000 at an interest rate of 6.3% which was compounded annually for 4 years. What total did you pay after 4 years? 

$38,304.90

200


2243

300

What is the y-intercept and growth factor for the function f(x)=2(3)x  

y-intercept=2

growth factor= 3

300

f(x)=.25(1.3)x

Does this functions represent exponential growth or decay? What is the percent growth/decay rate?

Exponential Growth

30%

300

In exponential functions, when b>1 this will cause an exponential growth or decay?

Exponential growth

300

$900 is invested in an account that pays 1.95%, compounded annually. Determine the value after 15 years.

$1202.41

300

What will be the cost in 17 years?

$32,313.27

400

What is the y-intercept and horizontal asymptote?

y-intercept = (0, 1)

asymptote = y=0


400

f(x)=a(.93)x

Does this functions represent exponential growth or decay? What is the percent growth/decay rate?

Exponential Decay

7%

400

f(x)=a(1.07)x

Does this functions represent exponential growth or decay? What's the percent growth/decay factor?

Exponential Growth.  7%.

400

$900 is invested in an account that pays 1.95%, compounded annually. Determine the amount of interest earned after 15 years.

$302.41

400


16,941 people

500

Write an exponential equation that has an asymptote of 4 and points down.

y=-a(b)x +4

500

Ms. Wiggins purchased a car for 26,400 and every year it decays by 12%. What can she expect the value of her car to be after 3.5 years?  


f(x)=26400(.88)3.5=$16,876.92

500

Annual sales of a fast food restaurant are $530,000 and increasing at a rate of 5%. What will the annual sales be in 6 years? 

530,000(1.05)=$710,250.69

500

$2000 is invested in a compound interest account. After 5 years, it is worth $2341.15. Determine its annual compound interest rate.

3.2%

500

If you put $500.00 into an account and the account earns 3% interest, compounded quarterly. How much will be in the account after 5 years?

$580.59

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