1. 4.6 Exponential Growth and Decay

2. Exponential Growth
Exponential growth occurs when a quantity increases by the same percent r in each time period t.
Remember if b > 1, then you will have growth.
Growth rate
Initial value
Growth factor
Time Period
(in years)
3.4.2: Graphing Exponential Functions

3. Exponential Growth Exponential Decay
Money compound interest Money Depreciation
y=A = the future value of the investment/loan, including interest C=P = the principal investment amount (the initial deposit or loan amount) r = the annual interest rate (decimal) n = the number of times that interest is compounded per year t = the number of years the money is invested or borrowed for

4. Compounded interest
Annually means 1 time per year
Bi-annually means 2 times per year
Quarterly means 4 times per year
Monthly means 12 times per year
Bi-monthly means 24 times per year
If the problem does not mention any of these then assume n = 1
T is in years, so if you have months then divide by 12,
Example: 5 months would be 5/12 for T