化简求值:(sin60/sin20)-(cos60/cos20)

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化简求值:(sin60/sin20)-(cos60/cos20)化简求值:(sin60/sin20)-(cos60/cos20)化简求值:(sin60/sin20)-(cos60/cos20)(sin

化简求值:(sin60/sin20)-(cos60/cos20)
化简求值:(sin60/sin20)-(cos60/cos20)

化简求值:(sin60/sin20)-(cos60/cos20)
(sin60cos20)/(sin20cos20)-(cos60sin20)/(sin20cos20)
=(sin60cos20-cos60sin20)/(sin20cos20)
利用两角和公式,和半角公式
=2sin(60-20)/2sin20cos20
=2sin40/sin40
=2