WAEC 2015 Mathematics · Question 43
Given that logx 64 = 3, evaluate x log8
Options
- A.6
- B.9
- C.12
- D.24
Answer: C. 12
Explanation written with AI and checked against the answer key
Analyze the question We are given log_x 64 = 3, which means x is the base of the logarithm. We must find x · log₂ 8. Step 1: Find x log_x 64 = 3 means x³ = 64, so x = 4. Step 2: Evaluate log₂ 8 Since 8 = 2³, log₂ 8 = 3. Step 3: Multiply x · log₂ 8 = 4 × 3 = 12 Checking against the options Tip: Convert a log statement to index form with this rule: log_b N = k means b^k = N. Then use powers of 2 (2, 4, 8, 16, 32, 64) to evaluate logs quickly. Also, read the question carefully, because "x log₂ 8" here means x multiplied by log₂ 8.AI can make mistakes. Report anything that looks wrong.
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