Edexcel Mathematics June 2018 · Paper 1 · Question 8 · ExamRizz

ExamRizzEdexcel MathematicsMathematics

June 2018 · Paper 1 · Question 8 · 5 marks

8. The depth of water, D metres, in a harbour on a particular day is modelled by the formula D = 5 + 2 sin (30t)° 0  t < 24 where t is the number of hours after midnight. A boat enters the harbour at 6:30 am and it takes 2 hours to load its cargo. The boat requires the depth of water to be at least 3.8 metres before it can leave the harbour. (a) Find the depth of the water in the harbour when the boat enters the harbour. (1) (b) Find, to the nearest minute, the earliest time the boat can leave the harbour . (Solutions based entirely on graphical or numerical methods are not acceptable .) (4) 21

Lesson: Definitions of Sine, Cosine and Tangent and Exact Values