问题 解答题
计算:
(1)
27
-2cos30°+
1
2
-2-|1-
3
|
(2)
a2
a+1
-a+1
答案

(1)

27
-2cos30°+(
1
2
-2-|1-
3
|

=3

3
-2×
3
2
+4-(
3
-1)

=

3
+5;

(2)

a2
a+1
-a+1

=

a2
a+1
-
(a-1)(a+1)
a+1

=

1
a+1

单项选择题
填空题