1)!!!!! tgx-sin2x=0

tgx-sin2x=0
tgx-2tgx/(1+tg^2x)=0
tgx(1-2/(1+tg^2x)=0
tgx=0
x=πk;k€Z
1-2/(1+tg^2x)=0
(1+tg^2x-2)/(1+tg^2x)=0
1+tg^2x#0
tg^2x-1=0
tg^2x=1
tgx=1;x=π/4+πk
tgx=-1;x=-π/4+πk;k€Z
ответ πk;π/4+πk;-π/4+πk;k€Z