Question

cos(3x-87)=1/2 найдите x

Answer 1

3x -87 = +-arcCos1/2 + 2πk , k ∈ Z
3x - 87 = +-π/3 + 2πk , k ∈ Z
3x = 87  +- π/3 + 2πk , k ∈Z
x = 29 +-π/9 + 2πk/3 , k ∈ Z