Higher November 2022 Paper 6 Q19
19 PQS and QRS are triangles.
Not to scale
PQ = 9 cm, QR = 8 cm and RS = 13 cm.
Angle QPS = 30° and angle PSQ = 15°.
Calculate angle QSR.
Give your answer correct to 1 decimal place.
You must show your working. [6]
| Answer | Marks | Part marks and guidance | |
|---|---|---|---|
| Accept answers that round to 25.7 with correct working | 6 | M2 for \(\frac{9 \times \sin 30}{\sin 15}\) oe or M1 for \(\frac{9}{\sin 15} = \frac{[\ldots]}{\sin 30}\) oe AND M3 for correct cos rule with cos as the subject \(\frac{13^2 + (their\ 17.386\ldots)^2 - 8^2}{2 \times 13 \times (their\ 17.386\ldots)}\) oe or M2 for the above (M3) with one error or wrong angle selected or for \(8^2 = 13^2 + (their\ 17.386\ldots)^2 - 2 \times 13 \times (their\ 17.386\ldots) \times \cos[\ldots]\) or M1 for the above (M2) with one error or wrong angle selected If 0 or 1 or 2 scored, instead award SC3 for 25.7 (or an answer rounding to 25.7) with no working or insufficient working If 0 or 1 scored, instead award SC2 for 0.898 to 0.902 with no working or insufficient working If 0 scored, instead award SC1 for [QS =] 17.3 to 17.4 with no working | “Correct working” requires evidence of at least M1 AND M2 (17.386…) (0.900…) e.g. for \(\frac{8^2 + (their\ 17.386\ldots)^2 - 13^2}{2 \times 8 \times (their\ 17.386\ldots)}\) e.g. for \(13^2 = 8^2 + (their\ 17.386\ldots)^2 - 2 \times 8 \times (their\ 17.386\ldots) \times \cos[\ldots]\) |