(x+2y)(x-y)(x-2y)(x+y) 计算 急
问题描述:
(x+2y)(x-y)(x-2y)(x+y) 计算 急
答
原式=[(x+2y)(x-2y)][(x-y)(x+y)]
=(x²-4y²)(x²-y²)
=x⁴-5x²y²+4y⁴