问题 解答题
计算:
(1)(1+
1
x
x2-1
x

(2)
a2
a-1
-a-1
答案

(1)原式=

x+1
x
x
(x+1)(x-1)
=
1
x-1

(2)原式=

a2-(a+1)(a-1)
a-1
=
1
a-1

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