化简sin(60°+α)-sin(60°-α)
证明:(1) sin(360°-α)=-sinα
一道数学化简题sin 90°-α/sin α =
证明:sin(360°-α)=-sinα
化简sin(α+180°)cos(-α)sin(-α-180°)
化简 sin²α
化简:4sin(60°-A)*sinA*sin(60°+A).
化简sin(x+60°)+2sin(x-60°)-3
计算:sin方10°+sin方20°+sin方30°+sin方40°+sin方50°+sin方60°+sin方70°+s
化简cos(90°-α)/sin(270°-α)*sin(360°-α)*sin(180°-α)
求sin²20°+sin80°sin40°,并且要用sin(α+β)sin(α-β)=sin²α-s
sin²60° 怎么算
sin平方60°等于多少?