Question

sin(47pi/6)
tg(25pi/4)
ctg(27pi/4)
cos(21pi/4)

Answer 1

sin(47π/6)=sin(6π+11π/6)=-sinπ/6=-1/2
tg(25π/4)=tg(6π+π/4)=1
ctg(27π/4)=ctg(6π+3π/4)=-1
cos(21π/4)=cos(4π+5π/4)=-√2/2

Answer 2

Спасибо.