sin2a= 2tga / (1+tg^2(a))=1
Сделаем замену tg(a)=z
2z / (1+z^2) = 1
2z=1+z^2
z^2 - 2z + 1 = 0
( z - 1)^2 =0
z - 1 = 0
z = 1
tg(a) = 1
sin2a= 2tga / (1+tg^2(a))=1
Сделаем замену tg(a)=z
2z / (1+z^2) = 1
2z=1+z^2
z^2 - 2z + 1 = 0
( z - 1)^2 =0
z - 1 = 0
z = 1
tg(a) = 1