问题
解答题
计算: (1)(a2-1)÷(1-
(2)
|
答案
(1)(a2-1)÷(1-
)1 a
=(a+1)(a-1)÷a-1 a
=(a+1)(a-1)×a a-1
=a2+a;
(2)
+a2-1 a2-2a+1
÷a2a2-a2 a-2
=
+(a+1)(a-1) (a-1)2
×a2 a-2 1 a
=
+a+1 a-1 a a-2
=
.2a2-2a-2 (a-1)(a-2)