问题
解答题
先化简,再求值:(
|
答案
3x-2(x-2)>5①
≥1②7-2x 2
∵解不等式①得:x>1,
解不等式②得:x≤
,5 2
∴不等式组的解集为:1<x≤
,5 2
∴不等式组的整数解是x=2,
(
-x x-1
)÷x x2-1 x2-x x2-2x+1
=[
-x(x+1) (x+1)(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
当x=2时,原式=
=2 2+1
.2 3