A logarithm is the opposite of a power. Expressed mathematically, x is the logarithm of n to the base b if b^x = n, in which case one writes x = log_bn. For example, 2³ = 8; therefore, 3 is the logarithm of 8 to base 2, or 3 = log₂ 8. In the same fashion, since 10² = 100, then 2 = log₁₀ 100. 

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