Z = tg x z³ +z² -3z-3 =0 Z²(Z+1)-3 (Z+1)=0 (Z+1)(Z²-3)=0 tgx +1 =0 и tg²x-3 =0 tgx =-1 tg²x=3 или tg x = √3 x=3π/4 + πn x=π/3 +πn