sin13п/6=sin (2+1/6 )*p=sin p/6=1/2
cos 405=cos(360+45)=cos 45 =√2 / 2
tg(-11п/6)=tg(p/6)=1/2 : √3/2=1/√3
ctg5п/4=cos5p/4 : sin5p/4 =-√2/2 : -√2/2=1
sin13п/6=sin (2+1/6 )*p=sin p/6=1/2
cos 405=cos(360+45)=cos 45 =√2 / 2
tg(-11п/6)=tg(p/6)=1/2 : √3/2=1/√3
ctg5п/4=cos5p/4 : sin5p/4 =-√2/2 : -√2/2=1