题目内容
计算或化简:
(1)(-1)0+|2-
|+2
sin60°;
(2 )
+
.
(1)(-1)0+|2-
| 3 |
| 3 |
(2 )
| 1 |
| x-1 |
| 2 |
| 1-x2 |
分析:(1)由零指数幂,绝对值以及特殊角的三角函数值,即可得(-1)0=1,|2-
|=2-
,sin60°=
,然后利用整式的混合运算法则求解即可求得答案;
(2)首先通分,然后利用同分母的分式相加减的运算法则求解即可求得答案.
| 3 |
| 3 |
| ||
| 2 |
(2)首先通分,然后利用同分母的分式相加减的运算法则求解即可求得答案.
解答:解:(1)(-1)0+|2-
|+2
sin60°
=1+2-
+2
×
=3-
+3
=6-
;
(2)
+
=
-
=
=
=
.
| 3 |
| 3 |
=1+2-
| 3 |
| 3 |
| ||
| 2 |
=3-
| 3 |
=6-
| 3 |
(2)
| 1 |
| x-1 |
| 2 |
| 1-x2 |
=
| 1 |
| x-1 |
| 2 |
| (x+1)(x-1) |
=
| x+1-2 |
| (x+1)(x-1) |
=
| x-1 |
| (x+1)(x-1) |
=
| 1 |
| x+1 |
点评:此题考查了实数的混合运算与分式的加减运算.此题比较简单,注意掌握运算顺序是解此题的关键,注意要细心.
练习册系列答案
相关题目