问题
解答题
(1)计算:(-
(2)先化简,再求值:
|
答案
(1)原式=-2+1+
×3 3 3
=-2+1+1
=0;
(2)原式=
÷x(x-2) (x-1)(x+1) x2-1-(2x-1) x+1
=
•x(x-2) (x-1)(x+1) x+1 x(x-2)
=
,1 x-1
当x=
时,原式=1 2
=-2.1
-11 2
(1)计算:(-
(2)先化简,再求值:
|
(1)原式=-2+1+
×3 3 3
=-2+1+1
=0;
(2)原式=
÷x(x-2) (x-1)(x+1) x2-1-(2x-1) x+1
=
•x(x-2) (x-1)(x+1) x+1 x(x-2)
=
,1 x-1
当x=
时,原式=1 2
=-2.1
-11 2