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Here are some properties of exponents, followed by some simple and more difficult examples:
Properties of Logarithms
- logaa = 1 Example: log33=1
- loga1 = 0 Example: log51=0
- logaab=b Example: log335=5
- alogab=b Example: 3log32=2
- logaxr = (r)logax Example: log5x2 = (2)log5x
- loga(xy) = loga(x)+loga(y) Example: loga(5x) = loga(5)+loga(x)
- loga(x/y) = loga(x) - loga(y) Example: loga(5/x) = loga(5) - loga(x)
- y = logax is the same as x=ay Example: y=log6x -> x=6y
- ln(x) = logex where e ≈ 2.71828
Examples of logarithms
Simplify the following logarithmic problems
1) log28 = log223 = 3log22 = 3(1) = 3
Where properties 1,3, and 5 were utilized
2) log4(4x2) = log4(4)+log4(x2) = 1+2log4(x)
Where properties 1, 5, and 6 were utilized
Expand the following logarithm
3) 
Notice that everything in the numerator received a (+) sign in front of the newly expanded logarithm and everything in the denominator received a (-) sign. Furthermore,

This represents the expanded form of the logarithm. Keep in mind you may be asked to go the other way, starting with an expanded logarithm and working back to a single logarithm.
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