1.Sin-(x)=sin 2пи 2.Sin(пи/2-x)=sin пи/4
1. sin(-x) = sin(2π) sin(-x) = 0 -x = πn, n ∈ Z x=-πn, n ∈ Z 2. sin(π/2-x)=sin(π/4) sin(π/2-x) = sqrt(2)/2 π/2-x = π/4 + 2πn, n∈Z и 3π/4 + 2πn -x = -π/4 + 2πn и π/4 + 2πn, n∈Z x = +- π/4 + 2πn, n∈Z