Question

вычислить tg 15градусов

Answer 1

tg15=tg(45-30)=(tg45-tg30)/(1+tg45*tg30)=(1-√3/3)/(1+1*√3/3)=
=((3-√3)/3)/((3+√3)/3)=(3-√3)(3+√3)=(3-√3)²/(3²-(√3)²)=(9-6√3+3)/(9-3)=
=(12-6√3)/6=2-3√3