Additional Mathematics 0606 / Trigonometry / 3.613.61: Sec/cosec and compound-angle equations0606/22/M/J/25 — Question 9 · 10 marksMark as done · Save for later · Show all solutions(a)Solve the equation 3 sec 3x=cosec 3x\sqrt{3}\,\mathrm{sec}\,3x = \mathrm{cosec}\,3x3sec3x=cosec3x for −120∘⩽x⩽120∘-120^{\circ} \leqslant x \leqslant 120^{\circ}−120∘⩽x⩽120∘.[5]▸ Answer(b)Solve the equation 2 cos(y+π3)+sin(y+π3)=sin y+cos y2\,\mathrm{cos}\left(y+\dfrac{\pi}{3}\right) + \mathrm{sin}\left(y+\dfrac{\pi}{3}\right) = \mathrm{sin}\,y + \mathrm{cos}\,y2cos(y+3π)+sin(y+3π)=siny+cosy for 0⩽y⩽2π0 \leqslant y \leqslant 2\pi0⩽y⩽2π.[5]▸ Answer▸ Official mark scheme← 3.60: Area between chord and curve3.62: Binomial expansion coefficients →
