问题
解答题
(1)计算:2+(
(2)化简求值:(
|
答案
(1)原式=2+1-4=-1;
(2)原式=
÷3-(x+1)(x-1) x-1
=-(x+2)(x-2) (x-1)2
•(x+2)(x-2) x-1
=-x+1,(x-1)2 (x+2)(x-2)
∵x≠1,x2-1=0,
∴x=-1,
则原式=1+1=2.
(1)计算:2+(
(2)化简求值:(
|
(1)原式=2+1-4=-1;
(2)原式=
÷3-(x+1)(x-1) x-1
=-(x+2)(x-2) (x-1)2
•(x+2)(x-2) x-1
=-x+1,(x-1)2 (x+2)(x-2)
∵x≠1,x2-1=0,
∴x=-1,
则原式=1+1=2.