题目内容
计算:
(1)
-x+1
(2 )
-
.
(1)
| x2 |
| x+1 |
(2 )
| x+1 |
| x2-1 |
| 1+x |
| 1-x |
考点:分式的加减法
专题:
分析:(1)首先通分,再根据同分母的分式相加减,分母不变,分子相加减即可;
(2)首先通分,再根据同分母的分式相加减,分母不变,分子相加减即可;
(2)首先通分,再根据同分母的分式相加减,分母不变,分子相加减即可;
解答:解:(1)原式=
-
=
-
=
;
(2)原式=
+
=
=
=
.
| x2 |
| x+1 |
| x-1 |
| 1 |
| x2 |
| x+1 |
| x2-1 |
| x+1 |
| 1 |
| x+1 |
(2)原式=
| x+1 |
| x2-1 |
| (1+x)2 |
| x2-1 |
| x+1+1+2x+x2 |
| (x+1)(x-1) |
| x2+3x+2 |
| (x+1)(x-1) |
| x+2 |
| x-1 |
点评:此题主要考查了分式的加减,关键是正确进行通分,最后再把结果化简.
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