问题 填空题
化简(
x2-1
x2-2x+1
+
1-x
x+1
x
x-1
的结果是______.
答案

原式=[

(x+1)(x-1)
(x-1)2
-
x-1
x+1
]•
x-1
x

=

x+1
x
-
(x-1)2
x(x+1)

=

(x+1)2-(x-1)2
x(x+1)

=

4x
x(x+1)

=

4
x+1

故答案为:

4
x+1

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