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The Change-of-Base Formula

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The change-of-base formula computes any logarithm from a borrowed base: log_b(M) = log(M)/log(b), with the same base upstairs and down.

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log₂(32) = log(32)/log(2) ≈ 1.505/0.301 = 5 — the calculator's two buttons reaching any base.

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A quotient of logs is change of base, never the log of a quotient.

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