Identify the relationship: Identify the relationship between the base of the logarithm and the number.The base of the logarithm is 3, and we need to find the exponent that 3 must be raised to in order to get 81.
Express 81 as a power: Express 81 as a power of 3.81 is 3 raised to the power of 4, since 3×3×3×3=81.
Apply the definition of a logarithm: Apply the definition of a logarithm.Since 81 is 34, we can write log381 as log3(34).
Use the property of logarithms: Use the property of logarithms that logb(bx)=x. According to this property, log3(34) simplifies to 4.
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