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(x+y)^2(x-y)^2-(x-y)(x+y)(x^2+y^2),其中x=0.5,y=-2

题目详情
(x+y)^2(x-y)^2-(x-y)(x+y)(x^2+y^2),其中x=0.5,y= -2
▼优质解答
答案和解析
原式=[(x++y)(x-y)]²-(x²-y²)(x²+y²
=(x²-y²)²-(x²-y²)(x²+y²)
=-(x²-y²)(x²-y²-x²-y²)
=-2y²(x²-y²)
=-2x²y²+2y^4
=-2+32
=30