Помогите решить:12,14,16,18,20,22,24,26,28,30

12 sin(x-π/4)=0 x-π/4=πn x=π/4+πn,n∈z 14 sin(x-π/3)=0 x-π/3=πn x=π/3+πn,n∈z 16 tg(π/3-x)=0 -tg(x-π/3)=0 x-π/3=πn x=π/3+πn,n∈z 18 cosx=-√2/2 x=+-3π/4+2πn,n∈z 20 cos(x-π)=-1 -cosx=-1 cosx=1 x=2πn,n∈z 22 1/2*sin2x=√3/4 sin2x=√3/2 2x=(-1)^n*π/3+πn x=(-1)^n*π/6+πn/2,n∈z 24 1-cos(x/3+π/3)=1/2 cos(x/3+π/3)=1/2 x/3+π/3=+-π/3+2πn x/3=-2π/3+2πn U x/3=2πn x=+-2π+6πn U x=6πn,n∈z 26 tg3x=4 3x=arctg4+πn x=1/3*arctg4+πn/3,n∈z 28 cosxcos2x=0 cosx=0⇒x=π/2+πn,n∈z cos2x=0⇒2x=π/2+πn⇒x=π/4+πn/2,n∈z 30 2cos²x=1 2cos²x-1=0 cos2x=0 2x=π/2+πn⇒x=π/4+πn/2,n∈z