1.16: Solve trigonometric equations

4PM1/1R/November/2020 — Question 10 · 11 marks

Solve
(a) sin(x+π3)=32,0x2π,\mathrm{sin}\left(x+\frac{\pi}{3}\right)=\frac{\sqrt{3}}{2}, \qquad 0\leq x\leq2\pi,
giving your answers in terms of π\displaystyle \pi,
(3)
(b) 3sinθ+5cosθ=0,360θ360,3\mathrm{sin}\,\theta+5\mathrm{cos}\,\theta=0, \qquad -360^\circ\leq\theta\leq360^\circ,
giving your answers to the nearest degree,
(3)
(c) 1+sin2y=2cos22y,180y0.1+\mathrm{sin}\,2y=2\mathrm{cos}^2 2y, \qquad -180^\circ\leq y\leq0^\circ.
(5)