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2tana=3tanb,求证tan(a-b)=sin2b/5-cos2b.求详细解答.
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要是能咋说啊?
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辅助角公式中是arctan(a/b) 还是arctan(b/a)?
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cos(a b) = cosacosb-sinasinb,cos(a-b) = cosacosb sinasinb,
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tanα=b/a
2tana=3tanb,求证tan(a-b)=sin2b/5-cos2b.求详细解答.
要是能咋说啊?
辅助角公式中是arctan(a/b) 还是arctan(b/a)?
cos(a b) = cosacosb-sinasinb,cos(a-b) = cosacosb sinasinb,
tanα=b/a