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Logarithmic Functions | Calculus I - Lumen Learning
For any b> 0, b ≠ 1, the logarithmic function with base b, denoted log b, has domain (0, ∞) and range (∞, ∞), and satisfies. log b (x) = y if and only if b y = x. For example, log 2 (8) = 3 since 2 3 = 8, log 10 (1 100) = 2 since 10 2 = 1 10 2 = 1 100, log b (1) = 0 since b 0 = 1 for any base b> 0.