sin(π/18)sin(5π/18)sin(-65π/18)=

sin(π/18)sin(5π/18)sin(-65π/18)= sinπ/18sin5π/18 sin（- 65π/18 sin之间为乘法sinπ/18sin5π/18 sin（- 65π/18sin之间为乘法 计算:sin[arc*sin(3/5)+arc*sin(7/18)] 计算,sin(π/12)-sin(5π/12)+2sin(π/8)sin(3π/8) 化简sin(4π-a)*sin(5π-a)=? sin(-5π/3)等于 sin(5π/12)= sin(-5π/12)是多少 sin(π/5)怎么算? 求sin(π/14)*sin(3π/14)*sin(5π/14)的值 求sin^2π/5+sin^23π/5的值sin方 Sin（5π+α)=sin(π+α)=-sinα正确吗? 比较sin(25π/18)和sin(31π/18) 的大小, sin(-π/18)和sin(-π/10)比大小急``````速度````` 利用公式C(α-β),S(α-β)证明sin(π-α)=sinα S (sin 5x) (sin 3x) dx = sin(2π+a) ,sin(π+a),sin(5π+a) 的区别为什么sin(2π+a) =sina sin(π+a)=-sina 若sin(π+a)