| Exam Board | OCR MEI |
|---|---|
| Module | C2 (Core Mathematics 2) |
| Marks | 4 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Arithmetic Sequences and Series |
| Type | Sigma notation: direct numerical evaluation |
| Difficulty | Easy -1.2 This is a straightforward question requiring only direct substitution into a recurrence relation (part i) and basic summation of a simple expression (part ii). Both parts are routine calculations with no problem-solving or conceptual insight required, making it easier than average A-level questions. |
| Spec | 1.04e Sequences: nth term and recurrence relations1.04g Sigma notation: for sums of series |
| Answer | Marks | Guidance |
|---|---|---|
| (i) [answer] | 1 | |
| 27 or ft from their 11 | 1 | |
| (ii) [answer] | 2 | M1 for \(1\times2 + 2\times3 + 3\times4\) soi, or 2,6,12 identified, or for substituting \(n=3\) in standard formulae |
## Question 9:
| (i) [answer] | 1 | |
| 27 or ft from their 11 | 1 | |
| (ii) [answer] | 2 | **M1** for $1\times2 + 2\times3 + 3\times4$ soi, or 2,6,12 identified, or for substituting $n=3$ in standard formulae |9 (i) Find the second and third terms of the sequence defined by the following.
$$\begin{aligned}
t _ { n + 1 } & = 2 t _ { n } + 5 \\
t _ { 1 } & = 3
\end{aligned}$$
(ii) Find $\sum _ { k = 1 } ^ { 3 } k ( k + 1 )$.
\hfill \mbox{\textit{OCR MEI C2 Q9 [4]}}