化简:sin²(α+π)cos(-α+π)/tan(α+π)tan(α+2π)cos²(-α-π)1.cos(27°+α)cos(33°-α)-sin(27°+α)sin(33°-α) 2.sin²(α+π)cos(-α+π)/tan(α+π)tan(α+2π)cos²(-α-π)

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化简:sin²(α+π)cos(-α+π)/tan(α+π)tan(α+2π)cos²(-α-π)1.cos(27°+α)cos(33°-α)-sin(27°+α)sin(33°-α) 2.sin²(α+π)cos(-α+π)/tan(α+π)tan(α+2π)cos²(-α-π)
化简:sin²(α+π)cos(-α+π)/tan(α+π)tan(α+2π)cos²(-α-π)
1.cos(27°+α)cos(33°-α)-sin(27°+α)sin(33°-α)
2.sin²(α+π)cos(-α+π)/tan(α+π)tan(α+2π)cos²(-α-π)

化简:sin²(α+π)cos(-α+π)/tan(α+π)tan(α+2π)cos²(-α-π)1.cos(27°+α)cos(33°-α)-sin(27°+α)sin(33°-α) 2.sin²(α+π)cos(-α+π)/tan(α+π)tan(α+2π)cos²(-α-π)
1.cos(27°+α)cos(33°-α)-sin(27°+α)sin(33°-α)=cos[(27°+α)+(33°-α)]=cos60°=0.5
2.sin²(α+π)cos(-α+π)/[tan(α+π)tan(α+2π)cos²(-α-π)]=-sin^2αcosα/[tanα*tanα*cos^2α]=-sin^2αcosα/sin^2α=-cosα
说实在的,看了你第二个表达式的描述就可以明白你问这么简单的问题的原因了.数学很重要,努点力吧

1.cos(27°+α)cos(33°-α)-sin(27°+α)sin(33°-α)=cos[(27°+α)+(33°-α)]=cos60°=0.5
2.sin²(α+π)cos(-α+π)/[tan(α+π)tan(α+2π)cos²(-α-π)]=-sin^2αcosα/[tanα*tanα*cos^2α]=-sin^2αcosα/sin^2α=-cosα

1.cos(27°+α)cos(33°-α)-sin(27°+α)sin(33°-α) =cos60°=0.5
sin²(α+π)cos(-α+π)/tan(α+π)tan(α+2π)cos²(-α-π)sin^2αcosα/[tanα*tanα*cos^2α]=-sin^2αcosα/sin^2α=-cosα