1. Today’s Agenda
 Attendance
 Sections
4.1
/ Announcements

2. Payday!
You just got a job! You will work for 30 days. You may
choose between three pay rates.
Rate Plan A pays $200,000 a day.
Rate Plan B pays $50,000 your first day and provides
you with a $10,000 raise each subsequent day. (For
instance, you earn $60,000 on the second day, $70,000 the
third day, and so forth.)
Rate Plan C pays 2 cents the first day and doubles every
subsequent day. (For instance, you earn 4 cents on the
second day, 8 cents on the third day, and so forth)

3. Payday!
Rate Plan A pays $200,000 a day.

4. Payday!
Rate Plan B pays $50,000 your first day and provides you with a
$10,000 raise each subsequent day. (For instance, you earn $60,000
on the second day, $70,000 the third day, and so forth.)

5. Payday!
Rate Plan C pays 2 cents the first day and doubles every
subsequent day. (For instance, you earn 4 cents on the second day,
8 cents on the third day, and so forth)

6. Payday!
Rate Plan C pays 2 cents the first day and doubles every
subsequent day. (For instance, you earn 4 cents on the second day,
8 cents on the third day, and so forth)

7. Payday!
Rate Plan C pays 2 cents the first day and doubles every
subsequent day. (For instance, you earn 4 cents on the second day,
8 cents on the third day, and so forth)

8. Exponential Functions
Variable is in
exponent
f ( x) b
x
base
*Just because a function has an exponent,
doesn’t mean it is an exponential function

9. f ( x) 3x
2
4x
2x 1
g ( x) 3
h( x) 3 x
3
h(t ) 3x 2
f ( x) 3 2
x2 1
1

10. Basic Graphs
f ( x)
2
x

11. Basic Graphs
f ( x)
2
x

12. Basic Graphs
f ( x)
1
2
x

13. Basic Graphs
f ( x)
2
x 3

14. Basic Graphs
f ( x)
2
x
3

15. This is
considered
Exponential
Growth

16. What
common point
do they all
pass through?

17. This is
considered
Exponential
Decay

19. Exponential Functions with Initial
Values
Some unit of
time (usually)
f ( x)
Initial Value,
or initial
population
a b
x
Rate of
growth or
decay

20. Exponential Functions with Initial
Values
Some unit of
time (usually)
P (t )
Initial Value,
or initial
population
P0 r
t
Rate of
growth or
decay

21. …Quick Algebra Check!...
3 2
1
2
4
2
3

22. A bacteria starts with an initial count of 3000
and doubles every hour.
How many bacteria after 3.5 hours?
When will there be 25,000 bacteria?

23. A bacteria starts with an initial count of 3000.
An antibiotic is introduced, causing half of the
bacteria to die off each hour.
How many bacteria after 3.5 hours?
When will there be 500 bacteria?

24. Classwork
• Page 220
1 – 6 All
19, 20 – 30 all,
45, 49