A mechanical linkage is set at an obtuse angle ϕ\phiϕ. The equilibrium position of the linkage is determined by the equation
(4sinϕ+cosϕ)2+(2sinϕ−2cosϕ)2=10.4 (4 \sin \phi + \cos \phi)^2 + (2 \sin \phi - 2 \cos \phi)^2 = 10.4 (4sinϕ+cosϕ)2+(2sinϕ−2cosϕ)2=10.4Find the exact value of sinϕ\sin \phisinϕ. Fully justify your answer.
Practise AQA A Level Maths 1.8 E: Trigonometry with exam-style questions for A Level Maths. 239 questions covering 1.8.1 Trigonometric definitions, rules and radians, 1.8.2 Small angle approximations (A-level only), 1.8.3 Trigonometric functions and exact values, 1.8.4 Reciprocal and inverse trigonometric functions (A-level only), 1.8.5 Trigonometric identities, 1.8.6 Compound and double angle formulae (A-level only), 1.8.7 Solving trigonometric equations, 1.8.8 Proofs with trigonometric identities, and 1.8.9 Trigonometry in context, matched to the AQA A Level Maths (7357) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.
