Graphical Exponential Functions

1. Graphical Exponential Functions March 25, 2013

2. Problem of the Day – March 25 If 8x 92y =81(212y) what is the value of x? 2 4 8 12 16

3. Solution of the Day – March 25

4. Questions from Practice Problems?

5. Example #1 A A) A graph describing a population of bacteria that doubles every week, at t=0, P=1000

6. Example #1 B B) A graph describing a population of bacteria that triples every week, at t=0, P=1000

7. Example #1

8. Let’s examine fish population growth ... • http://www.otherwise.com/population/exponent.html • http://www.otherwise.com/population/exponent.html

9. Examining various graphs with the same a value but different r values we can see this results in a horizontal stretch

10. Examining various graphs with the same r value but different a values we can see this results in a vertical stretch

11. Example #2 A car worth $23000 when purchased loses 12% of its value each year. a) Determine its value after 4.5 years

12. Example #2 b) A car worth $23000 when purchased loses 12% of its value each year. b) When would it have a value of $15000

13. Example #3 a) A property is purchased for $45000 and it increases in value by 8% per year. Determine a) Its value after 12 years

14. Example #3 b) A property is purchased for $45000 and it increases in value by 8% per year. Determine b) How long before the value is $75000

15. Example #4 a) In 2005 Cindy invests $5000 in a guaranteed investment that yields 8% interest per year, paid annually a) Write an equation describing this growth

16. Example #4 b) In 2005 Cindy invests $5000 in a guaranteed investment that yields 8% interest per year, paid annually b) Determine the value of her investment in 2015

17. Example #4 c) In 2005 Cindy invests $5000 in a guaranteed investment that yields 8% interest per year, paid annually c) Hong long will it take to triple?

18. Practice Problems Text p. 123 #52 (c,d) Handout – Modeling Exponential Relations