Ответы и объяснения

2014-04-11T23:28:45+04:00
Tg435+tg375 = tg(360+75)+tg(360+15) = tg75 + tg 15 = sin(75+15) / (cos75*cos15) sin(75+15) = sin90 = 1 cos75*cos15 = (cos60 + cos90) / 2 = (1/2 +0)/2 = 1/4   sin(75+15) / (cos75*cos15) = 1/(1/4) = 4