A28­2Notes.notebook
October 27, 2015
Algebra 2
Ch.8 Notes Page 46
P46 8­2 Properties of Exponential Functions
Aug 19­6:20 AM
Families of Exponential Functions
Parent Function:
Stretch ( | a | > 1 )
Shrink ( 0 < | a | < 1 )
Reflection ( a < 0 )
Translation:
Combined:
y = bx
y = abx
y = bx ­ h + k (vertical by k)
(horizontal by h)
y = abx ­ h + k
Nov 20­7:19 AM
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A28­2Notes.notebook
October 27, 2015
Graphing y = abx 0 < | a | < 1 Shrink
| a | > 1 Stretch
a = 1
a = .25 Shrink
a = 4 Stretch
Gets Wider
Gets Narrower
Nov 21­8:56 AM
Reflecting y = abx Graph y = (1/2)2x and y = (­1/2)2x Label the Asymptote
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A28­2Notes.notebook
October 27, 2015
Translating y = abx Graph y = 8 (1/2)x Horizontal Asymptote is y = 0
Graph y = 8 (1/2)x + 2 + 3
Shift 2 Units Left and 3 Units Up
Horizontal Asymptote is y = 3
(It shifts Up with the + 3)
Nov 20­7:19 AM
ex Exponential Functions with Base e are useful for describing continuous growth or decay.
e is irrational
e comes from y = (1 + 1/x)x
e is the asymptote of the function e ≈ 2.71828
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A28­2Notes.notebook
October 27, 2015
Continuously Compounded Interest Formula
You invest $1,050 at an annual interest rate of 5.5% compounded continuously. How much money will you have in the account after five years?
Nov 20­7:20 AM
Half­Life
The half­life of a radioactive substance is the time it takes for half of the material to decay. A hospital prepares a 100­mg supply of technetium­99m, which has a half­life of 6 hours. Write an exponential function to find the amount of technetium­99m that remains after 75 hours.
Remember each half­life is 6 hours. (75/6 = 12.5)
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A28­2Notes.notebook
October 27, 2015
HW #47
8­2 P442 #2,5,9,12,14,17,19,20,21,23,24,25,39
Please put your name and class period at the top of
the homework. Also include the homework number.
Aug 19­6:25 AM
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