Higher November 2020 Paper 1 Q12
12.
(a) Find the next term of this sequence.
\(\dfrac{3}{2},\quad -\dfrac{9}{4},\quad \dfrac{27}{8},\quad -\dfrac{81}{16},\quad \ldots\) [2]
(b) The \(n\)th term of a sequence is \(\left(2\sqrt{3}\right)^n\).
Find and simplify the 3rd term of this sequence. [2]
Find and simplify the 3rd term of this sequence. [2]
(c) Find the \(n\)th term of this sequence.
1·5, 3, 5·5, 9, 13·5, ... [2]
| Scheme | Marks | Comments |
|---|---|---|
| \(\dfrac{243}{32}\) | B2 | B1 for a numerator of 243 or a denominator of 32 or for \(-\dfrac{81}{16}\times-\dfrac{3}{2}\) si; implied by e.g. \(-\dfrac{81^{\times-3}}{16_{\times2}}\) |
| Scheme | Marks | Comments |
|---|---|---|
| \(24\sqrt{3}\) | B2 | B1 for \(2^3\times\left(\sqrt{3}\right)^3\) or better |
| Scheme | Marks | Comments |
|---|---|---|
| \(\dfrac{n^2}{2} + 1\) oe | B2 | B1 for \(\dfrac{n^2}{2} + k,\quad k \ne 1\) |
| (6) |