已知cos(15°+α)=3/5,α为锐角,求tan(435°-α)+sin(α-165°)/cos(195°+α)*sin(105°+α)

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已知cos(15°+α)=3/5,α为锐角,求tan(435°-α)+sin(α-165°)/cos(195°+α)*sin(105°+α)

已知cos(15°+α)=3/5,α为锐角,求tan(435°-α)+sin(α-165°)/cos(195°+α)*sin(105°+α)
已知cos(15°+α)=3/5,α为锐角,求tan(435°-α)+sin(α-165°)/cos(195°+α)*sin(105°+α)

已知cos(15°+α)=3/5,α为锐角,求tan(435°-α)+sin(α-165°)/cos(195°+α)*sin(105°+α)
tanα=cosα=sinα/cosα 所以sinα=cosα^2 又因为sinα^2+cosα^2=1 所以sinα^2+sinα=1 sinα=(-1+-./(1+4))/2=(-1+./5)/2和 =(-1-./5)/2