化简-sin14分之5派*sin14分之3派*sin14分之派

题目

化简-sin14分之5派*sin14分之3派*sin14分之派

答案

-sin(5π/14)*sin(3π/14)*sin(π/14)=-sin(5π/14)*sin(3π/14)*sin(π/14) *cos(π/14)/cos(π/14)=-sin(2π/14)*sin(3π/14)*(1/2)sin(2π/14)/cos(π/14)=-(1/4)sin(4π/14)cos(4π/14)/cos(π/14)=-(1/8)sin(8...