O-LevelMathematicsTrigonometry4024/21 · Oct/Nov 2017 · Q38 Marks
The diagram shows the positions of three towns, A, B and C. B is due north of A and the bearing of C from A is 220°. AB = 25 km and AC = 38km.
- (a)Find the bearing of A from C.[1]
- (b)Show that BC = 59.4km correct to 3 significant figures.[3]
- (c)Calculate the bearing of C from B.[4]
This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.
Mark scheme
Marking points from the official mark scheme (Oct/Nov 2017). The mark or mark type is shown in brackets.
- [1] 040
- [3] M2 or M1 for 25² + 38² – 2 × 25 × 38 × cos(360 - 220)
- [3] BC = √252 +382 - 2×25×38cos(360-220)
- [3] BC = 59.36 to 59.37
- [4] B3 for 24.1 to 24.3[2...]
- [4] M2 for sin B = 38xsin(360-220) / 59.4 or M1 for sin B / 38 = sin(360-220) / 59.4
- [4] and M1 for 180 + their B
- [4] 204.1 to 204.3[2...]
Write your answer and get it marked
On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.
Sign up free →