Решите уравнение: а)sin x=-0,5√2 б)2cos2x-1=0 в)2sin(x/2-п/6)=-1

1/   sinx=-√2/2   x=(-1)ⁿ(-π/4)+πn   n∈Z
2/   cos2x=1/2  2x=+-π/3+2πn    x=+-π/6+πn   n∈Z
3/   sin(x/2-π/6)=-1/2   x/2=(-1)ⁿ(-π/6)+πn+π/6
x=(-1)ⁿ(-π/3)+2πn+π/3    n∈Z