问题 解答题

计算:

(1)(3x2y)3•(-5y);

(2)[(x+y)2-y(2x+y)-4x]÷2x.

答案

(1)原式=27x6y3•(-5y)=-135x6y4

(2)原式=(x2+y2+2xy-2xy-y2-4x)÷2x

=(x2-4x)÷2x

=

1
2
x-2.

选择题
单项选择题