题目内容
化简| a+1 | ||
a+1-
|
| a-1 | ||
|
分析:本题需先对二次根式进行分母有理化,再化简合并即可求出答案.
解答:解:
+
=
+
=
+
=
=
=1
故答案为1
| a+1 | ||
a+1-
|
| a-1 | ||
|
=
(a+1)(a+1+
| ||
| (a+1)2-(1-a2) |
(a-1)(a-1-
| ||
| (a-1)2-(1-a2) |
=
a+1+
| ||
| 2a |
a-1-
| ||
| 2a |
=
a+1+
| ||||
| 2a |
=
| 2a |
| 2a |
=1
故答案为1
点评:本题主要考查了二次根式的化简求值问题,在解题时要注意a的取值范围是解题的关键.
练习册系列答案
相关题目