化简数学函数化简[(cos²(π/2+α)-sin²(7π/2+α))/(sinα+cosα)]-sin(7π-α)化简这道数学题,
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化简数学函数化简[(cos²(π/2+α)-sin²(7π/2+α))/(sinα+cosα)]-sin(7π-α)化简这道数学题,(图1)
======以下答案可供参考======
供参考答案1:
原式=(sin²α-cos²α)/(sinα+cosα)-sin(π-α)
=sinα-cosα-sinα
=-cosα
供参考答案2:
[(cos²(π/2+α)-sin²(7π/2+α))/(sinα+cosα)]-sin(7π-α)
=(sin²α - cos²α)/(sinα+cosα) - sin(π-α)
=sinα - cosα - sinα
=-cosα