1) cosx=1/√2
x=±arccos 1/√2+2πn,n∈Z
x=±π/4+2πn, n∈Z
2)tg2x=-√3/3
2x=arctg(-√3/3)+πn,n∈Z
2x=-π/6+πn
x=-π/12+πn/2, n∈Z
1) cosx=1/√2
x=±arccos 1/√2+2πn,n∈Z
x=±π/4+2πn, n∈Z
2)tg2x=-√3/3
2x=arctg(-√3/3)+πn,n∈Z
2x=-π/6+πn
x=-π/12+πn/2, n∈Z