Sin (7π/6)-cos(11π/6)+ctg(11π/4); (sin(α-π)-cos(π/2-α))/cos(α-π)+sin(3π/2-α) ; α-альфа

1)-1/2-sqrt(3)/2-1=(3-sqrt(3))/2

1) Sin (7π/6)-cos(11π/6)+ctg(11π/4)= sin(п/6)-cos(п/6)+ctg(-п/4)= -(1/2+v3/2)

2) (sin(α-π)-cos(π/2-α))/cos(α-π)+sin(3π/2-α)= sin(-(π-a))-cos(π/2-a)/ cos(-(π-a))+sin(3π/2-a)=0