Sin3x = 2/3
3x = arcsin2/3 + 2πn, n∈Z
x = 1/3arcsin2/3 + 2πn/3, n∈Z
Cosx/2 = 3/2
x/2 = arccos3/2 + 2πn, n∈Z
x = 2arccos3/2 + 4πn,n∈Z
tgx/3 = 1/4
x/3 = arctg1/4 + πn, n∈Z
x = 3arctg1/4 + 3πn, n∈Z
Ctg2x = 4
2x = arcctg4 + πn, n∈Z
x = 1/2arcctg4 + πn/2, n∈Z