engineering mathematics MCQ #4939

The solution of 2cos²(x) - 1 = 0 is

engineering mathematics MCQ #4939

  1. Question 1

    Q1. The solution of 2cos²(x) - 1 = 0 is

    • A) nπ ± π/4
    • B) 2nπ ± π/4
    • C) nπ ± π/3
    • D) 2nπ ± π/3

    Answer: nπ ± π/4

    Explanation: 2cos²(x) - 1 = cos(2x) = 0, hence 2x = (2n+1)π/2, giving x = nπ ± π/4.