问题 解答题
计算:
2
a2-1
+
1
a+1
答案

2
a2-1
+
1
a+1

=

2
(a+1)(a-1)
+
1
a+1

=

2
(a+1)(a-1)
+
a-1
(a+1)(a-1)

=

2+a-1
(a+1)(a-1)

=

a+1
(a+1)(a-1)

=

1
a-1

单项选择题 共用题干题
单项选择题 A3/A4型题