engineering mathematics MCQ #4935

The solution of cos(2x) + cos(x) = 0 is

engineering mathematics MCQ #4935

  1. Question 1

    Q1. The solution of cos(2x) + cos(x) = 0 is

    • A) 2nπ ± 2π/3
    • B) 2nπ/3 or 2nπ ± π/3
    • C) nπ or 2nπ ± 2π/3
    • D) 2nπ ± π/3

    Answer: nπ or 2nπ ± 2π/3

    Explanation: Use the identity cos(2x) = 2cos²(x) - 1, then simplify and solve the resulting quadratic equation.