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(1)解分式方程:1x−1=2x2−1(2)先化简(1−1x−1)÷x2−4x+4x2−1,然后从-2≤x≤2的范围内选取一个合适的整数作为x的值代入求值.

题目详情
1
x−1
2
x2−1

(2)先化简(1−
1
x−1
x2−4x+4
x2−1
,然后从-2≤x≤2的范围内选取一个合适的整数作为x的值代入求值.
1
x−1
11x−1x−1
2
x2−1
22x2−1x2−1x2−1x2−12−1
(1−
1
x−1
x2−4x+4
x2−1
,然后从-2≤x≤2的范围内选取一个合适的整数作为x的值代入求值.
1
x−1
11x−1x−1
x2−4x+4
x2−1
x2−4x+4x2−4x+4x2−4x+4x2−4x+42−4x+4x2−1x2−1x2−1x2−12−1
▼优质解答
答案和解析
(1)方程的两边同乘(x+1)(x-1),得:x+1=2,
解得:x=1.
检验:把x=1代入(x+1)(x-1)=0,即x=1不是原分式方程的解,
故原分式方程无解;

(2)原式=
x−1−1
x−1
(x+1)(x−1)
(x−2)2

=
x+1
x−2

∵(x+1)(x-1)≠0,x-2≠0,
∴x≠±1且x≠2,
当x=0时,原式=-
1
2
x−1−1
x−1
x−1−1x−1−1x−1−1x−1x−1x−1•
(x+1)(x−1)
(x−2)2

=
x+1
x−2

∵(x+1)(x-1)≠0,x-2≠0,
∴x≠±1且x≠2,
当x=0时,原式=-
1
2
(x+1)(x−1)
(x−2)2
(x+1)(x−1)(x+1)(x−1)(x+1)(x−1)(x−2)2(x−2)2(x−2)22
=
x+1
x−2

∵(x+1)(x-1)≠0,x-2≠0,
∴x≠±1且x≠2,
当x=0时,原式=-
1
2
x+1
x−2
x+1x+1x+1x−2x−2x−2,
∵(x+1)(x-1)≠0,x-2≠0,
∴x≠±1且x≠2,
当x=0时,原式=-
1
2
1
2
111222.