问题
解答题
计算: (1)
(2)
|
答案
(1)
-2cos30°+(27
)-2-|1-1 2
|3
=3
-2×3
+4-(3 2
-1)3
=
+5;3
(2)
-a+1a2 a+1
=
-a2 a+1 (a-1)(a+1) a+1
=
.1 a+1
计算: (1)
(2)
|
(1)
-2cos30°+(27
)-2-|1-1 2
|3
=3
-2×3
+4-(3 2
-1)3
=
+5;3
(2)
-a+1a2 a+1
=
-a2 a+1 (a-1)(a+1) a+1
=
.1 a+1