问题 解答题
(1)计算:-22+(
1
2
-1
0+2sin30°       
(2)化简:
x-1
x
÷(x-
1
x
答案

(1)-22+(

1
2
-1
0+2sin30° 

=-4+1+1

=-2;      

(2)

x-1
x
÷(x-
1
x

=

x-1
x
x
(x+1)(x-1)

=

1
x+1

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