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If logₖ(A) * log₅(k) = 3, then A is equal to (given k > 0, k not equal to 1).
- 5k³
- k³
- 125
- 243
Correct answer: 125
Solution
By the chain rule: logₖ(A) * log₅(k) = log₅(A). Setting this equal to 3 gives log₅(A) = 3, so A = 5³ = 125.
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