问题 解答题
化简计算:
(1)1-
a-1
a
÷
a2-1
a2+2a

(2)
x-2
x2
÷(1-
2
x
)
答案

(1)原式=1-

a-1
a
a(a+2)
(a+1)(a-1)

=1-

a+2
a+1

=

a+1-(a+2)
a+1

=-

1
a+1

(2)原式=

x-2
x2
÷
x-2
x

=

x-2
x2
x
x-2

=

1
x

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