Let θ1 and θ2 (where θ1 < θ2)are two solutions of 2cot2θ – 5/sinθ + 4 = 0, θ ∈ [0, 2] then ∫cos23θdθ for θ ∈ [θ1 + θ2] is equal to
(1) π/3
(2) 2π/3
(3) π/9
(4) π/3 + 1/6
Answer is (1) π/3
