Year 12 Logarithms and Exponential Equations Worksheet — Level 3 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 12 exponentials & logarithms worksheet.
Success TutoringWorksheetsAnswer sheetYear 12 · Mathematics · Exponentials & LogarithmsYear 12 Logarithms and Exponential Equations Worksheet — Level 3 — Practice Set 4 — Answers
logₐ y = x means ax = y. Log laws: log a + log b = log ab; log a − log b = log (a ÷ b); log aⁿ = n log a.
1.Write as a single logarithm: log 9 + log 7
Answer: log 63
log a + log b = log ab
2.Write as a single logarithm: log 9 − log 3
Answer: log 3
log a − log b = log (a ÷ b)
3.Evaluate log₅ .
Answer: -2
5-2 =
4.Evaluate log₅ 125.
Answer: 3
53 = 125
5.Evaluate log₃ 81.
Answer: 4
34 = 81
6.Evaluate log₂ 64.
Answer: 6
26 = 64
7.Write as a single logarithm: log 7 + log 7
Answer: log 49
log a + log b = log ab
8.Write as a single logarithm: log 3 + log 4
Answer: log 12
log a + log b = log ab
9.Evaluate log₂ 8.
Answer: 3
23 = 8
10.Solve: 102x = 100
Answer: x = 1
- 100 = 102
- 2x = 2
- x = 1
11.Write as a single logarithm: log 2 + log 7
Answer: log 14
log a + log b = log ab
12.Evaluate log₃ .
Answer: -1
3-1 =
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