C-08-Q162mediumsingle_mcqIn 0<θ<2π0 < \theta < 2\pi0<θ<2π, the equation 2sin2θ+3cosθ=02\sin^{2}\theta + 3\cos\theta = 02sin2θ+3cosθ=0 gives cosθ\cos\thetacosθ equal to —a−12-\dfrac{1}{2}−21b32\dfrac{3}{2}