2sin(-π/3)+2cos(-π/6)+2ctg(π/4)=-2sin(π/3)+2cos(π/6)+2ctg(π/4)=

=-2 × (√3)/2 +2 ×(√3)/2 + 2 × 1= 2

( sin(-x)=-sinx , cos(-x)=cosx , sin(π/3)=(√3)/2 , cos(π/6)=

= (√3)/2,tg(π/4)=ctg(π/4)=1)