Помогите пожалуйста!!!! СрочноРешите неравенство

N1

cos(x)^2 - sqrt(3)sin(x)cos(x) = 0

cos(x)(cos(x) - sqrt(3)sinx) = 0

cos(x) = 0 cos(x) - sqrt(3)sin(x) = 0

2(cos(x)/2 - sqrt(3)sin(x)/2) = 0

cos(x)/2 - sqrt(3)sin(x)/2 = 0

sin(/6)cos(x) - cos(/6)sin(x) = 0

sin(/6 - x) = 0

x = /2 + n /6 - x = k

- x = -/6 + k

x = /6 - k

x = /6 + k

Ответ : x = /2 + n, x = /6 + k

N2

cos(x) =lt; -0,5

cos(x) = -0,5

x = -2/3 + 2n = 4/3 + 2n

x = 2/3 + 2n

cos(x) =lt; -0,5

x [2/3 + 2n; 4/3 + 2n]

Ответ : [2/3 + 2n; 4/3 + 2n]