问题
解答题
先化简
|
答案
原式=
•x-1 x+2
-(x+2)(x-2) x(x-2) x x-1
=
-x-1 x x x-1
=(x-1)2-x2 x(x-1)
=
,1-2x x2-x
当x=
时,原式=1 2
=0.1-2× 1 2
-1 4 1 2
先化简
|
原式=
•x-1 x+2
-(x+2)(x-2) x(x-2) x x-1
=
-x-1 x x x-1
=(x-1)2-x2 x(x-1)
=
,1-2x x2-x
当x=
时,原式=1 2
=0.1-2× 1 2
-1 4 1 2