问题 填空题
化简:
2a2b2
4a3b
=______;
x2-1
y
y2
x+1
=______.
答案

2a2b2
4a3b
=
b
2a

x2-1
y
y2
x+1

=

(x+1)(x-1)
y
y2
x+1

=y(x-1)

=xy-y,

故答案为:

b
2a
,xy-y.

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