Solve, for 0 ≤ x < 180°,
2cos2(2x - 10°) = 3sin(2x - 10°).
From Paper 2: Pure Mathematics 2
48 marks
(a) Express 5cos x - 12sin x in the form Rcos(x + α), where R > 0 and 0 < α < π/2. Give α to 4 decimal places.
(b) Hence solve 5cos x - 12sin x = 6.5 for 0 ≤ x < 2π.
From Paper 2: Pure Mathematics 2
1010 marks
(a) Prove that (1 - cos 2x)/(sin 2x) ≡ tan x.
(b) Prove that csc 2x + cot 2x ≡ cot x.
(c) Hence solve csc 2x + cot 2x = 2 for 0° < x < 360°, giving your answers to 1 decimal place.
Score 0 / 24 · 0 of 3 marked
This paper is written by Plasmo in the style of the Edexcel A-Level Maths exam. It is not a past paper and is not produced or endorsed by the exam board.