Question

求角19π/6的正弦,余弦,正切

Answer 1

19π/6=2π+π+π/6

所以

sin19π/6

=sin(2π+π+π/6)

=sin(π+π/6)

=-sinπ/6

=-1/2

cos19π/6

=cos(2π+π+π/6)

=cos(π+π/6)

=-cosπ/6

=-√3/2

tan19π/6

=tan(2π+π+π/6)

=tanπ/6

=√3/3