tg 435

Ответ от Іветик[гуру]
tg435+tg375=tg(360+75)+tg(15+360)=tg75+tg15=tg(45+30)+tg(30/2)=
= (tg45+tg30)/(1-tg30*tg45) + sin30 / (1+cos30)=
= (1+ √3/3)/ (1-1*√3/3) + 1/2 : (1+√3/2) =
= (3+√3)*3/3*(3-√3) + 1/(2+√3) =
=(3+√3)(3+√3)/(3-√3)(3+√3) + (2-√3)/(2+√3)/(2-√3)=
=(9+6√3+3)/(9-3) + (2-√3)/(4-3)=
=6(2+√3)/6+(2-√3)=(2+√3)+(2-√3)=4