1. Exponential Growth & Decay By: Kasey Gadow, Sarah Dhein & Emily Seitz

2. Thrift Shop Parody "Math Edition"

3. 3.2 Exponential Growth & Decay If a>0 and b>1 f is increasing therefore it's exponential growth and b is the growth factor. If a>0 and b<1 f is decreasing therefore it's exponential decay and b is the decay factor.

4. Examples Identifying Functions Is it a function? Yes? Give initial value and base. No? Why not? Yes, initial value 1, base 3 No, base should not be x. Yes, initial value -2, base 1.5

5. Examples continued Determine the formula using values from the table.

6. Exponential Population Model If r>0, then P(t) is an exponential growth function and it's is the base, 1+r. If r<0, the base 1+r <1, P(t) is an exponential decay function, 1+r is the decay factor.

7. Example Tell whether the population is an exponential growth or decay function, and find the constant percentage rate of growth or decay.

8. Half Life The amount of time it takes for half a sample to change from a radioactive state

9. Example Suppose the half-life of a certain radioactive substance is 20 days and there are 5 grams present initially. Find the time when there will be 1 gram of the substance remaining.