Prove the identity:
cos2xcosx+sinx≡cosx−sinx \frac{\cos 2x}{\cos x + \sin x} \equiv \cos x - \sin x cosx+sinxcos2x≡cosx−sinxPractise Edexcel A Level Maths 7.5 Proving Trigonometric Identities with exam-style questions for A Level Maths. 27 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.