问题 填空题
已知0<a<1,化简
a+
1
a
+2
-
a+
1
a
-2
=______.
答案

∵0<a<1,

a
1
a

∴原式=

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

=

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

=

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

单项选择题
单项选择题