Foundation November 2020 Paper 3 Q31
31 \(\mathbf{c} = \begin{pmatrix} 4 \\ 9 \end{pmatrix} \qquad \mathbf{d} = \begin{pmatrix} 2 \\ -5 \end{pmatrix}\)
Work out \(\quad 4\mathbf{c} + 3\mathbf{d}\) [2 marks]
| Answer | Mark | Comments |
|---|---|---|
| \((4\mathbf{c} =) \begin{pmatrix} 16 \\ 36 \end{pmatrix}\) or \((3\mathbf{d} =) \begin{pmatrix} 6 \\ -15 \end{pmatrix}\) or \((\text{answer} =) \begin{pmatrix} 22 \\ \ldots \end{pmatrix}\) or \((\text{answer} =) \begin{pmatrix} \ldots \\ 21 \end{pmatrix}\) | M1 | |
| \(\begin{pmatrix} 22 \\ 21 \end{pmatrix}\) | A1 |
Additional guidance
| Condone missing brackets and divisor lines for M mark | |
| Must see \(\begin{pmatrix} 22 \\ 21 \end{pmatrix}\) to award the A mark, condone divisor line | |
| Condone vectors written as coordinates eg (16, 36) eg (22, …) | M1 M1 |
| Allow 16 36 or 6 \(-15\) | M1 |
| 36 16 or \(-15\) 6 | M0 |
| 22 not indicated as \(x\) component or 21 not indicated as \(y\) component without other work for M1 | M0 |