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Grade 12 · Functions
Logarithms: The Complete Grade 12 Guide
MEMORANDUM
Name:
Class:
Date:
Mark
/ 20
Answer all questions. Show all your working — marks are awarded for method as well as the final answer. Teacher copy: accept any correct equivalent method.
- 1Evaluate log₂ 16. (evaluate)(2)24 = 16 → 4✓✓ (2)
- 2Evaluate log₃ 27. (evaluate)(2)33 = 27 → 3✓✓ (2)
- 3Evaluate log₁₀ 1000. (evaluate)(2)103 = 1000 → 3✓✓ (2)
- 4Write 53 = 125 in log form. (convert)(2)log₅ 125 = 3✓✓ (2)
- 5Write log₂ 32 = 5 in exponent form. (convert)(2)25 = 32✓✓ (2)
- 6Simplify log 2 + log 50. (laws)(2)log(2×50) = log 100 = 2✓✓ (2)
- 7Simplify log 200 − log 2. (laws)(2)log(2002) = log 100 = 2✓✓ (2)
- 8Write log 8 as a multiple of log 2. (laws)(2)log 23 = 3 log 2✓✓ (2)
- 9Evaluate log₂ 10 (change of base, 2 dp). (change base)(2)log10 ÷ log2 ≈ 3,32✓✓ (2)
- 10Solve 2ˣ = 20 (2 dp). (solve)(2)x = log20 ÷ log2 ≈ 4,32✓✓ (2)
TOTAL: 20 marks