Prove that:
sec4A−tan4A≡2sec2A−1\sec^4 A - \tan^4 A \equiv 2\sec^2 A - 1sec4A−tan4A≡2sec2A−1
Hence solve, for 0≤A≤3600 \leq A \leq 3600≤A≤360, the equation,
sec4A−tan4A=3 \sec^4 A - \tan^4 A = 3 sec4A−tan4A=3Practise Edexcel A Level Maths 6.4 Trigonometric Identities with exam-style questions for A Level Maths. 12 questions, matched to the Edexcel A Level Maths (9MA0) 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.