问题
解答题
(1)计算:(
(2)已知a2+2a-
|
答案
(1)原式=
-1+2 3
+1-2
×1 2 2 2
=
;13 2 12
(2)原式=[
-a-2 a(a+2)
]•a-1 (a+2)2 a+2 a-4
=
•a-4 a(a+2) 2 a+2 a-4
=
,1 a2+2a
∵a2+2a-
=0,3
∴a2+2a=
,3
∴原式=
=1 3
.3 3
(1)计算:(
(2)已知a2+2a-
|
(1)原式=
-1+2 3
+1-2
×1 2 2 2
=
;13 2 12
(2)原式=[
-a-2 a(a+2)
]•a-1 (a+2)2 a+2 a-4
=
•a-4 a(a+2) 2 a+2 a-4
=
,1 a2+2a
∵a2+2a-
=0,3
∴a2+2a=
,3
∴原式=
=1 3
.3 3