Решить а)cos4x=1 б)cos2x=-1 в)cos(x+П/3)=0
Решение а) cos4x = 1 4x = 2πk, k∈Z x = πk/2, k∈z б) cos2x= -1 2x = π + 2πn, n∈z x = π/2 + πn, n∈Z в) cos(x +π/3)=0 x + π/3 = π/2 + πm, m∈Z x = π/2 - π/3 + πm, m∈Z x = π/6 + πm, m∈Z