问题 解答题
计算
(1)20050-22+(
1
3
)-1
  
(2)
3
(x-1)2
-
3x
(x-1)2

(3)
4
a2-4
+
2
a+2
-
1
a-2

(4)
a2-1
a2+2a+1
÷
a2-a
a+1
答案

(1)原式=1-4+3

=0;

(2)原式=

3-3x
(x-1)2

=-

3(x-1)
(x-1)2

=-

3
x-1

(3)原式=

4+2(a-2)-(a+2)
(a+2)(a-2)

=

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

=

1
a+2

(4)原式=

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

=

1
a

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