A(-x+y)(x-y)B(x-y)(y-x)C(x+y)(x-2y)D(x+y)(-x+y)这些哪个能用平方差公式计算

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A(-x+y)(x-y)B(x-y)(y-x)C(x+y)(x-2y)D(x+y)(-x+y)这些哪个能用平方差公式计算
A(-x+y)(x-y)B(x-y)(y-x)C(x+y)(x-2y)D(x+y)(-x+y)这些哪个能用平方差公式计算

A(-x+y)(x-y)B(x-y)(y-x)C(x+y)(x-2y)D(x+y)(-x+y)这些哪个能用平方差公式计算
解;
平方差公式;(a+b)(a-b)=a²-b²
A(-x+y)(x-y)
B(x-y)(y-x)
C(x+y)(x-2y)
D(x+y)(-x+y)
A-(x-y)(x-y)不是
B(x-y)[-(x-y)]不是
C肯定不是
D(x+y)[-(x-y)]=y²-x²是
选D