A-Level MathematicsYear 2015Q9
MARKS Page nine 9. The blades of a wind turbine are turning at a steady rate. The height, h metres, of the tip of one of the blades above the ground at time, t seconds, is given by the formula h = 36sin(1·5t) – 15cos(1·5t) + 65. Express 36sin(1·5t) – 15cos(1·5t) in the form ksin(1·5t – a), where k > 0 and 0 < a < 2 π , and hence find the two values of t for which the tip of this blade is at a height of 100 metres above the ground during the first turn. [END OF QUESTION PAPER] 8 [BLANK PAGE] do not write on this page Page ten [BLANK PAGE] do not write on this page Page eleven [BLANK PAGE] do not write on this page Page twelve
Paper Source:NH_Mathematics_all_2015.pdf
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Exam Specification Info
This question is part of the UK A-Level Mathematics syllabus. In the actual exam, structured questions typically require linking specific keywords to gain full marks. Applaa helps you drill these topics.
Syllabus levelAdvanced Level (A-Level)
SubjectMathematics
Official MarksVariable (2–6 marks)