问题
解答题
先化简再求值:(x-
|
答案
原式=
÷x(x-3)-(x-4) x-3
,x2-4 x-3
=
•(x-2)2 x-3
,x-3 (x+2)(x-2)
=
;x-2 x+2
当x=5时,原式=
=5-2 5+2
.3 7
先化简再求值:(x-
|
原式=
÷x(x-3)-(x-4) x-3
,x2-4 x-3
=
•(x-2)2 x-3
,x-3 (x+2)(x-2)
=
;x-2 x+2
当x=5时,原式=
=5-2 5+2
.3 7