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计算:(1)(m-n-p)(-m-n-p)=(2)(x-y+z)^2-(x+y-z)^2=

题目详情
计算:(1)(m-n-p)(-m-n-p)= (2)(x-y+z)^2-(x+y-z)^2=
▼优质解答
答案和解析
(1)(m-n-p)(-m-n-p)
= (-n-p)²-m²
=n²-2np+p²-m²
(2)(x-y+z)^2-(x+y-z)^2
=(x-y+z+x+y-z)(x-y+z-x-y+z)
=2x*(2z-2y)
=4xz-4xy