问题 解答题
计算:(1)|-2|-(1+
2
)0+
4

(2)(a-
1
a
a2-2a+1
a
答案

(1)原式=2-1+2=3.

(2)原式=

a2-1
a
÷
(a-1)2
a
=
(a+1)(a-1)
a
×
a
(a-1)2
=
a+1
a-1

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