Ctg(П/2) + tg П - sin (2/3П) -cos (-П/2)+sinП
π ctg(π/2)=0; tgπ=0; sin(2π/3)=sin(π-π/3)=sin(π/3)=√3/2;
cos(-π/2)=cos(π/2)=0; sinπ=0
Значит, 0 + 0 - √3/2 - 0 + 0 = -√3/2