(tg(a) + 1)*(tg(b) + 1) = 2
просто перемножим и преобразуем
tg(a)*tg(b) + tg(a) + tg(b) + 1 = 2
tg(a) + tg(b) = 2 - 1 - tg(a)*tg(b)
tg(a) + tg(b) = 1 - tg(a)*tg(b)
(tg(a) + tg(b))/(1 - tg(a)*tg(b))=1
tg(a + b) = (tg(a) + tg(b))/(1 - tg(a)*tg(b)) табличная формула tg суммы
tg(a + b) = 1
a, b ∈ (0,π/2)
a + b = π/4
3.2*((a + b)/π)² = 3.2*(1/4)² = 3.2 : 16 = 0.2
ответ В
