1)cos x = -(√3/2) 2)sin x =√2/2 3)cos3x = √3/2 4)cos(x/2)= √3/2 5) sin(x/2)=√2/2 6)sin3x=√2/2 7)sin(x/3)=-√2

1
x=+-5π/6+2πn,n∈z
2
x=(-1)^n*π/4+πn,n∈z
3
3x=+-π/6+2πn
x=+-π/18+2πn/3
4
x/2=+-π/6+2πn
x=+-π/3+πn,n∈z
5
x/2=(-1)^n*π/4+πn
x=(-1)^n*π/2+2πn,n∈z
6
3x=(-1)^n*π/4+πn
x=(-1)^n*π/12+πn/3,n∈z
7
sin(x/3)=-√2<-1
нет решения

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