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Find p such that: {(3)^-2}^p=81

1 Answer

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Exponential and Logarithmic Equations

Answer:


p = -2

Explanation:

Given:


(3^(-2))^p = 81

Recall:


a^b = c \Leftrightarrow \log_a (c) = b


\log_a (b^c) = d \Leftrightarrow c \cdot \log_a (b) = d

Solving for
p:


(3^(-2))^p = 81 \\ ((1)/(3^2))^p = 81 \\ ((1)/(9))^p = 81 \\ \log_(1)/(9) (81) = p \\ p = \log_(1)/(9) (((1)/(81))^(-1)) \\ p = -\log_(1)/(9) ((1)/(81)) \\ p = -(2) \\ p = -2

User Mihai Potra
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