Evaluate log_9(27) − log_{27}(9).

Aptitude Logarithm Difficulty: Easy
Choose an option
  • A
    6 / 5
  • B
    5 / 6
  • C
    3
  • D
    32

Answer

Correct Answer: 5 / 6

Explanation

Introduction / Context:Translate both logs to a common base (e.g., natural log) or use base–exponent recognition to evaluate each term exactly, then subtract.

Given Data / Assumptions:27 = 3^3 and 9 = 3^2.

Concept / Approach:Compute each term via ln: log_9(27) = ln 27 / ln 9 = (3 ln 3)/(2 ln 3) = 3/2. Similarly, log_{27}(9) = ln 9 / ln 27 = (2 ln 3)/(3 ln 3) = 2/3.

Step-by-Step Solution:

log_9(27) − log_{27}(9) = 3/2 − 2/3 = (9/6 − 4/6) = 5/6

Final Answer:5 / 6

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