Skip to content

Course home

Trigonometry and Modelling

Trigonometry and Modelling

EasyMediumHard
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116
Question 113

A mechanical engineer models the efficiency, EEE, of a specialized turbine using the function

E(θ)=4cos⁡2θ+2cos⁡θ+6 E(\theta) = 4 \cos 2\theta + 2 \cos \theta + 6 E(θ)=4cos2θ+2cosθ+6

where θ \theta\,θ is the blade pitch angle in degrees.

Find all values of θ\thetaθ, for 0≤θ<360∘0 \le \theta < 360^\circ0≤θ<360∘, for which the efficiency is exactly 5. Give your solutions to one decimal place where appropriate.

(Solutions based entirely on graphical or numerical methods are not acceptable.)

[5]
Markscheme

Trigonometry and Modelling Questions

  1. A Level
  2. /Maths
  3. /Trigonometry and Modelling

137 exam-style questions on Edexcel A Level Maths Trigonometry and Modelling, covering 7.1 Addition Formulae, 7.2 Double Angle Formulae, 7.3 Solving Trigonometric Equations, 7.4 Simplifying a cos x +- b sin x, 7.5 Proving Trigonometric Identities, and 7.6 Modelling with Trigonometric Functions. Each one has a worked solution and a mark scheme showing where the marks go.

Question bank