证明2sin(60°+α)cos(60°-α)=√3/2+sin2α,麻烦写下具体步骤.
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证明2sin(60°+α)cos(60°-α)=√3/2+sin2α,麻烦写下具体步骤.证明2sin(60°+α)cos(60°-α)=√3/2+sin2α,麻烦写下具体步骤.证明2sin(60°+α
证明2sin(60°+α)cos(60°-α)=√3/2+sin2α,麻烦写下具体步骤.
证明2sin(60°+α)cos(60°-α)=√3/2+sin2α,麻烦写下具体步骤.
证明2sin(60°+α)cos(60°-α)=√3/2+sin2α,麻烦写下具体步骤.
左边=sin(60°+α)cos(60°-α)+sin(60°+α)cos(60°-α)
=[sin(60°+α)cos(60°-α)+cos(60°+α)sin(60°-α)]+[sin(60°+α)cos(60°-α)-cos(60°+α)sin(60°-α)]
=sin[(60°+α)+(60°-α)]+sin[(60°+α)-(60°-α)]
=sin120°+sin2α
=√3/2+sin2α
=右边 .
利用和差角公式化简 (2)sin(π/3+α)+sin(π/3-α)(2)sin(π/3+α)+sin(π/3-α)(3)cos(π/4+α)-cos(π/4-α)(4)cos(60°+α)+cos(60°-α)(5)sin(α-β)cosβ+cos(α-β)sinβ(6)cos(α+β)cosβ+sin(α+β)sinβ
证明2sin(60°+α)cos(60°-α)=√3/2+sin2α,麻烦写下具体步骤.
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