A student attempts to solve by multiplying both sides by and obtains only the equation

MATHEMATICS · Single correct · A Level · Mathematics · Trigonometry · Trigonometry

Problem

A student attempts to solve sin⁡θ (1−2sin⁡θ)=0 \sin\theta\,(1-2\sin\theta)=0 by multiplying both sides by csc⁡θ\csc\theta and obtains only the equation 1−2sin⁡θ=01-2\sin\theta=0. Which of the following values of θ\theta in 0≤θ<2π0\le\theta<2\pi is (are) missed by the student? (a) θ=π6,5π6\theta=\dfrac{\pi}{6},\dfrac{5\pi}{6} (b) θ=0,π\theta=0,\pi (c) θ=0,π,2π\theta=0,\pi,2\pi (d) θ=π2,3π2\theta=\dfrac{\pi}{2},\dfrac{3\pi}{2}

Related theory

Browse the problem library