For a real variable ttt, use the quotient rule and the known derivatives of sint \sin t\,sint and cost \cos t\,cost to demonstrate that:
Practise Edexcel A Level Maths 9.6 Differentiating Trigonometric Functions with exam-style questions for A Level Maths. 4 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.