В) tg(3π+π/4) Б) cos (6π+π/6) Г)sin900°+cos780°)
1)tg(3π+π/4)=tg (π/4)=1 2)cos(6π+π/6)=cos(π/6)=(√3)/2 3)sin 900°+cos 780°=sin(2.360°+180°)+cos(2.360°+60°)= =sin 180° + cos 60° = 0+0,5=0,5