1
1)tgx≥3
x∈[arctg3+πn;π/2+πn,n∈z)
x∈-arctg3;π/2) U [π+arctg3;3π/2) U[2π+arctg3;5π/2)
2)tgx<4<br>x∈(-π/2+πn;arctg4+πn,n∈z)
x∈(-π/2;arctg4) U (π/2;π+arctg4) U (3π/2;2π+arctg4)
3)tgx≤-4
x∈(-π/2+πn;-arctg4+πn,n∈z]
x∈(-π/2;-arctg4] U (π/2;π-arcgt4] U (3π/2;2π-arctg4] U (5π/2;3π-arctg4]
4)tgx>-3
x∈(-arctg3+πn,π/2+πn,n∈z)
x∈(-arctg3,π/2) U (π-arctg3,3π/2) U (2π-arctg3;5π/2) U (3π-arctg4;3π]
2
1)ctg(x/2)=-1/√3
x/2=5π/6+πn
x=5π/3+2πn,n∈z
2)ctg3x=1
3x=π/4+πn
x=π/12+πn/3,n∈z