Additional Mathematics 0606 / Trigonometry / 1.51.5: Period and sketch of a cosine graph0606/11/M/J/20 — Question 2 · 4 marksMark as done · Save for later · Show all solutions(a)Write down the period of 2cosx3−12\cos\tfrac{x}{3} - 12cos3x−1.[1]▸ Answer(b)On the axes below, sketch the graph of y=2cosx3−1y = 2\cos\tfrac{x}{3} - 1y=2cos3x−1 for −360∘≤x≤360∘-360^{\circ} \le x \le 360^{\circ}−360∘≤x≤360∘.[3]▸ Answer▸ Official mark scheme← 2.22: Sin–tan identity and sec–cot equation1.6: Secant identity and cosecant equation →
