3xy(-xy²+xy)-xy²(-3xy+2x-1)(2.25x-1.5xy+2.5y²)×(-4xy)(-2ab)3ab(1-b)-4a(b-b)²

问题描述:

3xy(-xy²+xy)-xy²(-3xy+2x-1)
(2.25x-1.5xy+2.5y²)×(-4xy)
(-2ab)3ab(1-b)-4a(b-b)²

(1)x²y²+ xy²
(2)-9x²y+6x²y²-10xy³
(3)-6a²b²+6a²b³
..不过话说就是应该自己算哈..