问题
解答题
化简求值：(
|
答案
(
-x+2 x2-2x
)÷x-1 x2-4x+4 x-4 x
=[
-x+2 x(x -2)
]•x-1 (x-2)2 x x-4
=[
-(x+2)(x-2) x(x-2)2
]•x(x-1) x(x-2)2 x x-4
=
•x2-4-x2+x x(x-2)2 x x-4
=
•x-4 x(x-2)2 x x-4
=
，1 (x-2)2
∵x=
=2+1 2- 3
，3
∴原式=
=1 (2+
-2)23
．1 3