Вычислите tg1гр, tg3гр, tg89градусов.

Tg1° * tg3° * tg5° *  ... * tg85° * tg87° * tg89° = (tg1° * tg89°) * (tg3° * tg87°) *
* (tg5° * tg85°) * ... tg45° = (tg1° * Ctg1°) * (tg3° * Ctg3°) * (tg5° * Ctg5°) *
* ...  * tg45° = 1 * 1 * 1 * * 1 = 1