1) cosX=-1
x=π+2πk,k∈z
2) sin2X=√3/2
2x=(-1)^k*π/3+πk
x=(-1)^k*π/6+πk/2,k∈z
3) 3ctg X/3=√3
ctgx/3=√3/3
x/3=π/6+πk
x=π/2+3πk,k∈z
4) 2sin(X/2+П/8)+√2=0
sin(x/2+π/8)=-√2/2
x/2+π/8=-π/4+2πk U x/2+π/8=-3π/4+2πk
x/2=-3π/8+2πk U x/2=-7π/8+2πk
x=-3π/4+4πk U x=-7π/4+4πk,k∈z
5) (1+cosX)(3-2cosX)=0
1+cosx=0
cosx=-1
x=π+2πk,k∈z
3-2cosx=0
cosx=1,5>1 нет решения