3/23/16

Objectives of Today's Class: 
Investigate logarithmic functions 

-a logarithmic functions is the inverse of an exponential function


http://www.sosmath.com/algebra/logs/log4/log4.html

(see Summer's post for information on the first side of the notes)

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THE SECOND PAGE OF NOTES…

First, we evaluated how to apply logarithms. Some examples included…

a) log39
To do this problem, you can rewrite it as 3^x=9 and then you just have to figure out what number goes in for x. In this case, x would equal 2 because 3 squared equals 9. This is one of the simpler problems. Now for a more difficult problem…

d) log48
Write it as 4^x=8. Then, you make the bases equal. In this case, we can set them as 2. So it would look like 2^2x=2^3. Then you would set up the exponents like an algebra problem and solve. So, 2x=3, divide 2 on each side and you get that x= 2/3. 

Second, we looked at common logs and how to solve/evaluate them. For example…

log 100 would equal 2 because 10 squared equals 100

log 1 would equal 0 because the only power that 10 could go to to equal 1 is 0

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Remember…

Common log= log base 10 

10^x=y is the same thing as log10y=x 

Ask yourself: 10 to what power will give you x?