A28­5NotesPart2.notebook
November 10, 2015
Algebra 2
Ch.8 Notes Page 50
P50 8­5 Exponential & Logarithmic Equations
(Part 2)
Aug 19­6:20 AM
Solving Logarithmic Equations
log (3x + 1) = 5
1. Write in Exponential Form
2. Solve for X
log (7 ­ 2x) = ­1
Nov 20­7:30 AM
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A28­5NotesPart2.notebook
November 10, 2015
Using Logarithmic Properties to Solve an Equation
2 log x ­ log 3 = 2
Log x is only defined for x > 0, so 10√3 or 17.32
log 6 ­ log 3x = ­2
Nov 20­7:31 AM
Evaluating Logarithms with any base
Change of Base Formula
For any positive numbers, M, b, and c...
b ≠ 1 and c ≠ 1
logb M = logc M
logc b
log6 12
Learned at the beginning of Chapter
Nov 20­7:30 AM
2
A28­5NotesPart2.notebook
November 10, 2015
Using the Change of Base Formula
Evaluate log3 15.
Then Convert log3 15 to a logarithm with base 2.
Evaluate log5 400.
Then Convert log5 400 to a logarithm with base 8.
Nov 20­7:30 AM
HW #52
8­5 P464 #25­28,33­38,44­47
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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