a) sin 13п/6 =sin(12π/6+π/6)=sin(2π+π/6)=sin π/6=1/2=0.5
б) tg (-11п/6) =-tg(11π/6)=-tg(12π/6-π/6)=-tg(2π-π/6)=tgπ/6=√3/3
в)cos п + ctg 4п/3 =-1+√3/3
г)tg п/4 ctg (-п/4) + cos 3п/2 sin п/2 =-tg π/4*ctg π/4+0*1=-√2/2*√2/2+0=-2/4=-1/2=-0.5
д) sin 405º + cos 225º tg 225º=sin(360+45)+cos(180+45)*tg(180+45)=sin45+(-cos45)*tg45=√2/2-√2/2*1=0