November 2021 Paper 2 Q11
11 Expand and simplify fully \(\quad (5x + 3y^2)(4x - y^2)\) [3 marks]
| Answer | Mark | Comments |
|---|---|---|
| 3 terms from \(20x^2 \quad -5xy^2 \quad (+)12xy^2 \quad -3y^4\) | M1 | may be seen in a grid |
| \(20x^2 - 5xy^2 + 12xy^2 - 3y^4\) | A1 | four correct terms in any order may be seen in a grid implied by correct answer |
| \(20x^2 + 7xy^2 - 3y^4\) | A1 | terms may be in any order |
Additional guidance
| Terms seen in a grid must have the correct signs | |
| Terms must be fully processed eg do not allow \(4x3y^2\) unless recovered | |
| \(xy^2\) may be \(y^2x\) throughout | |
| \(20x^2 + 7xy^2 - 3y^4\) followed by incorrect further work | M1A1A0 |