Logarithm laws

A logarithm asks "what power?": log₂ 8 = 3 because 2³ = 8.

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Rewrite as a power question.
Log laws: log a + log b = log ab; log a − log b = log (a ÷ b); n log a = log aⁿ.

Simplify log_3(729) − log_3(9).

log a − log b = log(a ÷ b) = log_3(81) = 4, since 3^4 = 81.

Answer: 4

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log of 1 is always 0.

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