问题
解答题
先化简,再求值:(1+
|
答案
(1+
)÷1 x-1
,x x2-1
=
×x-1+1 x-1
,(x-1)(x+1) x
=
×x x-1
,(x-1)(x+1) x
=x+1,
当x=-2时,
原式=-2+1,
=-1.
先化简,再求值:(1+
|
(1+
)÷1 x-1
,x x2-1
=
×x-1+1 x-1
,(x-1)(x+1) x
=
×x x-1
,(x-1)(x+1) x
=x+1,
当x=-2时,
原式=-2+1,
=-1.