先化简,再求值: ( x+2 x - x-1 x-2 )÷ x-4 x 2 -4x+4 ,其中x是不等

2024-11-23 06:21:15
推荐回答(1个)
回答(1):

原式=[
(x+2)(x-2)
x(x-2)
-
x(x-1)
x(x-2)
(x-2 ) 2
x-4

=
x 2 -4- x 2 +x
x(x-2)
×
(x-2 ) 2
x-4

=
x-4
x(x-2)
×
(x-2 ) 2
x-4

=
x-2
x

3x+7>1,
3x>-6,
x>-2,
∵x是不等式3x+7>1的负整数解,
∴x=-1,
把x=-1代入
x-2
x
中得:
-1-2
-1
=3.