sin(-4π/3)cos(-23π/6)tan(25π/4)=?

问题描述:

sin(-4π/3)cos(-23π/6)tan(25π/4)=?

=sin60cos30tan45=3/4

sin(-4π/3)cos(-23π/6)tan(25π/4)=
sin(-4派/3+2派)cos(-23派/6+4派)tan(25派/4-6派)=
sin(2派/3)cos(派/4)tan(派/4)=
((根号3)/2)*((根号2)/2)*1=
(根号6)/4