Leaving Cert Maths: Indices & logs
How often Indices & logs comes up on the Maths papers, every year it was asked, and questions to try.
HL Asked on 10 of the last 10 Higher Level papers, most recently in 2026. banker
Quick ones on Indices & logs.
- 16
- 5
- 6
- (log a)(log b)
- log (a + b)
- log (ab)
- 4
- 16
- 2
Show the answers
(a) 5
(b) log (ab)
(c) 4
Higher Level
Asked on 10 of the last 10 Higher Level papers, most recently in 2026. banker
Every paper, year by year
| Year | Where it came up |
|---|---|
| 2026 | Q5, Q8 |
| 2025 | Q3, Q5 |
| 2024 | Q6 |
| 2023 | Q3 |
| 2022 | Q4, Q9, Q10 |
| 2021 | Q3, Q9 |
| 2019 | Q3 |
| 2018 | Q7, Q9 |
| 2017 | Q4, Q7 |
| 2016 | Q3, Q4, Q8 |
Links open the State Examinations Commission’s paper for that year.
More Indices & logs questions
Indices & logs, 2 marks
log₃ 81 = ?
- 27
- 3
- 4
Show the answer
4
3 to what power gives 81? 3⁴ = 81, so the answer is 4.
Indices & logs, 2 marks
e^(ln 7) = ?
- e⁷
- 7
- ln 7
Show the answer
7
eˣ and ln x are inverse functions, so they undo each other: e^(ln 7) = 7.
Indices & logs, 2 marks
Change of base: log_b a = ?
- log a / log b
- log b / log a
- log (a/b)
Show the answer
log a / log b
It's in the tables. The logs on top and bottom can be any base, as long as it's the same one (e.g. both base 10).