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(1)计算:(−1)101+(π−3)0+(12)−1−(1−2)2(2)化简分式(xx−1−xx2−1)÷x2−xx2−2x+1,并从-1≤x≤3中选一个你认为适合的整数x代入求值.

题目详情
(1)计算:(−1)101+(π−3)0+(
1
2
)−1−
(1−
2
)2

(2)化简分式(
x
x−1
x
x2−1
x2−x
x2−2x+1
,并从-1≤x≤3中选一个你认为适合的整数x代入求值.
▼优质解答
答案和解析
(1)原式=-1+1+2-
2
+1=3-
2

(2)原式=
x(x+1)−x
(x+1)(x−1)
(x−1)2
x(x−1)
=
x2
(x+1)(x−1)
(x−1)2
x(x−1)
=
x
x+1

∵-1≤x≤3,且x为整数,
∴x=2时,原式=
2
3