问题
解答题
(1)计算:(
(2)先化简,再求值:(x-
|
答案
(1)原式=1-3-2+
-2×2 2 2
=1-3-2+
-2 2
=-4;
(2)原式=
×x-1 x x x+1
=
,x-1 x+1
当x=
+1时,原式=2
=2
+22
=2-2 2 2-4
-1.2
(1)计算:(
(2)先化简,再求值:(x-
|
(1)原式=1-3-2+
-2×2 2 2
=1-3-2+
-2 2
=-4;
(2)原式=
×x-1 x x x+1
=
,x-1 x+1
当x=
+1时,原式=2
=2
+22
=2-2 2 2-4
-1.2