问题 解答题
化简:①
18
-
9
2
-
3
+
6
3
+(
3
-2)0+
(1-
2
)
2

(
a
+
1
a
)2-(
a
-
1
a
)2
答案

18
-
9
2
-
3
+
6
3
+(
3
-2)0+
(1-
2
)
2

=3

2
-
3
2
2
-1-
2
+1+
2
-1,

=

3
2
2
+1;

(

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

=[

a
+
1
a
+(
a
-
1
a
)][
a
+
1
a
-(
a
-
1
a
)],

=2

a
×
2
a

=4.

单项选择题
单项选择题