Prove that:
sec4x−tan4x≡1+2tan2x\sec^4x - \tan^4x \equiv 1 + 2\tan^2xsec4x−tan4x≡1+2tan2x
Hence solve, for 0≤x≤3600 \leq x \leq 3600≤x≤360, the equation,
12 exam-style questions on Edexcel A Level Maths 6.4 Trigonometric Identities. Each one has a worked solution and a mark scheme showing where the marks go.