问题 解答题
化简:
(1)
x2
x-1
+
x
1-x

(2)(1+
4
a2-4
a
a-2
答案

(1)原式=

x2
x-1
-
x
x-1

=

x(x-1)
x-1

=x;

(2)原式=

a2
(a-2)(a-2)
×
a-2
a

=

a
a+2

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