Higher January 2019 Paper 2R Q3
3 Here are the first five terms of a number sequence \(S\).
10 16 22 28 34
(a) Find an expression, in terms of \(n\), for the \(n\)th term of this sequence. (2)
The \(n\)th term of a sequence \(T\) is given by \(n^2 - 3\)
There are numbers that are terms in both the sequence \(S\) and the sequence \(T\).
(b) Find one of these numbers. (2)
| Scheme | Marks |
|---|---|
| M1 | |
| \(6n + 4\) | A1 |
| (2) |
Notes
M1: for \(6n + k\) (\(k\) may be 0 or absent) oe
A1: oe eg \(10 + (n - 1)6\) or \(n \times 6 + 4\)
| Scheme | Marks |
|---|---|
| ...40, 46,... −2, 1, 6, 13, 22, 33 46 ... \(6n + 4 = n^2 - 3\) oe | M1 |
| e.g. 22 or 46 | A1 |
| (2) | |
| (4 marks) |
Notes
M1: continuing sequence and writing at least 5 terms of 2nd sequence – allow one error or
for a correct equation ft part (a)
A1: or other number in both sequences eg −2