Math Quiz
Card Set Information
Author:
Anonymous
ID:
125987
Filename:
Math Quiz
Updated:
2012-01-04 21:27:54
Tags:
Algebra
Folders:
Description:
Logs and Exponential Functions
Show Answers:
Product
logb + logb = logb(m*n)
Example of Product- log2^4 + log2^8
1. 2^x = 4
x=2
2. 2^x = 8
x=3
2 + 3 = 5
ANSWER
: log2^32 = 5
Quotient
logb^m - logb^n + logb(m/n)
Example of Quotient- log2^8 - log2^4
1. 2^x = 8
x = 3
2. 2^x = 4
x = 2
3 - 2 = 1
3. 8/4 = 2
ANSWER
: log2^2 = 1
Power
logb^m^^p = P(logb^m)
Example of Power
log3^729^^3 = 3(log3^729)
1. 3^x = 729
x = 6
2. 6 * 3 = 18
ANSWER
: x = 18
Change of Base Formula
logb^m = loga^m/loga^b
a = new base
Example of Change of Base Formula
log3^23
1. 3^x = 23
2. log^23/log^3 ~ 2.85
x ~ 2.85
ANSWER
: 3^2.85 ~ 22.89
Exponential Function
Give meanings of letters
f(x) = b^x
b-base, constant
x-exponent, independent variable
b>0, b doesn't equal 1
When you are given an exponential fuction with no (x) what do you do?
You fill (x) in with random numbers.
If you aren't given an (x) in an exponential function how do you write the domain?
You write "all real numbers."
What does domain stand for and what does range stand for?
Domain- x value
Range- y value
What happens to the domain and range in an inverse?
They switch places.
Exponential growth
f(x) = ab^x
a>0 and b>0
The function increases as x increases.
Exponential Decay
When 0<b<1
The function decreases as x increases.
Does this show exponential growth or decay? f(x) = 1.5^x
Exponential Growth
Does this show exponential growth or decay? f(x) = (.8^x)
Exponential growth because the base, .8 is less than 1.