Higher November 2020 Paper 6 Q20
20 Vector \(\mathbf{m} = \begin{pmatrix} 2 \\ k \end{pmatrix}\) and vector \(\mathbf{n} = \begin{pmatrix} 3 \\ 11 \end{pmatrix}\).
Vector \(2\mathbf{m} + \mathbf{n}\) is parallel to \(\begin{pmatrix} 1 \\ -1 \end{pmatrix}\).
Find the value of \(k\). [4]
| Answer | Marks | Part marks and guidance | |
|---|---|---|---|
| -9 | 4 | M2 for \(\begin{pmatrix} 7 \\ 2k + 11 \end{pmatrix}\) or M1 for \(\begin{pmatrix} 7 \\ \ \end{pmatrix}\) or \(\begin{pmatrix} \ \\ 2k + 11 \end{pmatrix}\) or \(\begin{pmatrix} 4 \\ 2k \end{pmatrix}\) M1 for (their \(2k + 11\)) = – (their 7) | their 7 must follow from their working for M2 and must not be -1 |