Question

Упростить выражение tg(x - П/4) - tg(x +П/4).

Answer 1

Решение
tg(x - π/4) - tg(x + π/4) = sin(x - π/4 - x - π/4) / [cosx * cosπ/4] =
= √2 sin(- π/2) / cosx = - √2 / cosx