化简:sin(π/4-α)cos(π/3-α)-cos(π/6+α)sin(π/4+α)=
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化简:sin(π/4-α)cos(π/3-α)-cos(π/6+α)sin(π/4+α)=
化简:sin(π/4-α)cos(π/3-α)-cos(π/6+α)sin(π/4+α)=
化简:sin(π/4-α)cos(π/3-α)-cos(π/6+α)sin(π/4+α)=
cos(π/6+α)=sin(π/3-α),sin(π/4+α)=cos(π/4-α)
所以,原式=sin(π/4-α)cos(π/3-α)-sin(π/3-α)cos(π/4-α)
=sin(π/4-α)cos(π/3-α)-cos(π/4-α)sin(π/3-α)
=sin[(π/4-α)-(π/3-α)]
=sin(-π/12)
=(√2-√6)/4
sin(π/4-α)cos(π/3-α)-cos(π/6+α)sin(π/4+α)
=sin(π/4-α)cos(π/3-α)-cos[(π/2-π/3)+α]sin[(π/2-π/4)+α]
=sin(π/4-α)cos(π/3-α)-cos[π/2-(π/3-α)]sin[π/2-(π/4-α)]
=sin(π/4-α)cos(π/3-α)-sin(π/3-α)cos(...
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sin(π/4-α)cos(π/3-α)-cos(π/6+α)sin(π/4+α)
=sin(π/4-α)cos(π/3-α)-cos[(π/2-π/3)+α]sin[(π/2-π/4)+α]
=sin(π/4-α)cos(π/3-α)-cos[π/2-(π/3-α)]sin[π/2-(π/4-α)]
=sin(π/4-α)cos(π/3-α)-sin(π/3-α)cos(π/4-α)
=sin(π/4-α)cos(π/3-α)-cos(π/4-α)sin(π/3-α)
=sin[(π/4-α)-(π/3-α)]
=sin(π/4-α-π/3+α)
=sin(π/4-π/3)
=sin(-π/12)
=-sinπ/12
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