问题 解答题
(1)计算:2-1+(-1)2013+(2013-π)0-sin30°
(2)化简:(1+
x2-1
x2-2x+1
1
x-1
答案

(1)原式=

1
2
-1+1-
1
2
=0;

(2)原式=

2x2-2x
(x-1)2
•(x-1)

=

2x(x-1)
(x-1)2
•(x-1)

=2x.

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