求Sin(π+π/6)Sin(2π+π/6)Sin(3π+π/6).Sin(2008π+π/6)的值

2sin π/6 =sin π/3,吗,求解释,还有-sin π/6=sin- π/6吗 sin (973/2π) ,sin (374/2) sin(374/6)求三角函数值, 求sin^2α+sin^2(π/3 +α)+sin^2(π/3 -α) sin(π-α)=-2sin(π/2+α),求sinα·cosα 求sin^2π/5+sin^23π/5的值sin方 已知sin(x+π/6)=1/3,求sin(5π/6-x)+sin^2(π/3-x) 已知sin(x+π/6)=1/4,求sin(5π/6-x)+sin^2(π/3-x) 求Sin(π+π/6)Sin(2π+π/6)Sin(3π+π/6).Sin(2008π+π/6)的值 sin（-19π/6）=?已知[3Sin(π+a)+Cos(π-a)]/4Sin(-a)-Sin(5π/2+a)=2，求tan a Sin(π+π/6)Sin(2π+π/6)Sin(3π+π/6).Sin(2008π+π/6)求值 sin^2(π/3-x)+sin^2(π/6+x) sin(α+π/6)=-4/5,α属于（-π/2,π/2),求sinα sin(a-π/6)=3/5,求sin(2a+π/6) 已知sin(a/2+π/6)=1/4求sin(π/6+a) sin 11π/6 已知sin(π/6+a)=（根号3）/3,求sin(2π/3+a)? sinπ/2是什么意思 计算,sin(π/12)-sin(5π/12)+2sin(π/8)sin(3π/8)