问题
解答题
先化简,再求值:(
|
答案
原式=[
-(x-3)(x+1) (x-1)(x+1)
]×x+1 x-1 x-1 x-3
=-
.4 x-3
当x=2
×2
×1=2时,2 2
原式=-
=4.4 2-3
先化简,再求值:(
|
原式=[
-(x-3)(x+1) (x-1)(x+1)
]×x+1 x-1 x-1 x-3
=-
.4 x-3
当x=2
×2
×1=2时,2 2
原式=-
=4.4 2-3