Higher January 2021 Paper 2R Q1
1 \(w = 5y^2 - y^3\)
(a) Work out the value of \(w\) when \(y = -2\) (2)
(b) Factorise fully \(8p^2 - 2p\) (2)
(c) Expand \(4t(3t - 2)\) (2)
(d) Expand and simplify \((5x - 2)(x + 4)\) (2)
| Scheme | Marks |
|---|---|
| \(5 \times (-2)^2 - (-2)^3\;(= 20 - {-8})\) | M1 |
| Correct answer scores full marks (unless from obvious incorrect working) Answer: 28 | A1 |
| (2) |
Notes
M1: for correct expression
or at least one of 20 or 5 × 4 or – – 8 or (+) 8
| Scheme | Marks |
|---|---|
| \(2p(4p - 1)\) | B2 |
| (2) |
Notes
B2: (B1 for \(p(8p - 2)\) or \(2(4p^2 - p)\) or \(2p(4p - 1)\) with two terms inside the bracket with one term correct.)
| Scheme | Marks |
|---|---|
| \(12t^2 - 8t\) | B2 |
| (2) |
Notes
B2: (B1 for \(12t^2\) or \(-8t\))
| Scheme | Marks |
|---|---|
| \(5x^2 + 20x - 2x - 8\) | M1 |
| Correct answer scores full marks (unless from obvious incorrect working) Answer: \(5x^2 + 18x - 8\) | A1 |
| (2) | |
| (8 marks) |
Notes
M1: for 4 correct terms (ignoring signs) or 3 correct terms with correct signs.
or \(5x^2 + 18x + \ldots\)
or \(\ldots + 18x - 8\)