问题 解答题
(1)计算:(
y
6x2
)2÷(-
y2
4x
)2
.          
(2)计算:
x2-2x+1
x2-1
÷
x-1
x2+x
答案

(1)原式=

y2
36x4
×
16x2
y4
=
4
9x2y2

(2)原式=

(x-1)2
(x+1)(x-1)
×
x(x+1)
x-1
=x.

单项选择题
单项选择题