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=397 exam-style questions on WJEC A Level Maths 1.5 Trigonometry, covering 1.5.1 Trigonometry, 1.5.2 Trigonometry, 1.5.3 Trigonometry, 1.5.4 Trigonometry, and 1.5.5 Trigonometry. Each one has a worked solution and a mark scheme showing where the marks go.