2. Alg2 Trgi lsn 72.notebook December 16, 2009
log(AB) = log A + log B
Example: 1) Find the value of
2) If log(5) = A and log(3) = B, what is log(15)?
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5. Alg2 Trgi lsn 72.notebook December 16, 2009
packet page 2
packet page 2
Law of In symbols How operations are treated when
logarithms to using logarithms
calculate
a product log (A * B) = log A + log B log of product = sum of logs
with logs, multiplication converts to addition
a quotient log (A ÷ B) = log A log B log of quotient = difference of logs
with logs, division converts to subtraction
a power log (A)n = n log A log of power = multiplier of log
with logs, a power converts to
multiplication
a root log (√A) =(1/n) log A log of root = multiplier of log
with logs, a root (fractional power) converts
to multiplication
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