1) 2x = +- pi/3 + 2pin
x = +- pi/6+pin
2) x = (-1)^n (pi/6) +pin
4) 2tg x + 1=0
tg x = -1/2
x = -arctg 1/2+ pin
1) 2x = +- pi/3 + 2pin
x = +- pi/6+pin
2) x = (-1)^n (pi/6) +pin
4) 2tg x + 1=0
tg x = -1/2
x = -arctg 1/2+ pin