问题
解答题
先化简,后求值:(1+
|
答案
原式=
×x+1 x
-2x (x+1)(x-1)
=
-21 x-1
=1-2x+2 x-1
=
;3-2x x-1
当x=
时1 4
原式=3-2× 1 4
-11 4
=3- 1 2 - 3 4
=-
.10 3
先化简,后求值:(1+
|
原式=
×x+1 x
-2x (x+1)(x-1)
=
-21 x-1
=1-2x+2 x-1
=
;3-2x x-1
当x=
时1 4
原式=3-2× 1 4
-11 4
=3- 1 2 - 3 4
=-
.10 3