Trigonometryhard · Past Paper
A man in a boat moving away from a cliff 100 m high takes 2 mins for elevation to change from 60 to 30. Speed?
A100/√3 m/min
B100√3 m/min
C50√3 m/min
D200/√3 m/min
✓ Correct Answer: A — 100/√3 m/min
d1 = 100/√3, d2 = 100√3. Distance = 100√3 - 100/√3 = 200/√3. Speed = (200/√3)/2 = 100/√3.
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