计算: (1)(−3/2x2y)2(2x2−4xy+7y2) (2)(-4x-3y2)(3y2-4x)
问题描述:
计算:
(1)(−
x2y)2(2x2−4xy+7y2)3 2
(2)(-4x-3y2)(3y2-4x)
答
(1)原式=
x4y2(2x2-4xy+7y2),9 4
=
x6y2−9x5y3+9 2
x4y4;63 4
(2)原式=(-4x-3y2)(-4x+3y2),
=(-4x)2-(3y2)2,
=16x2-9y4.