题目内容
| lim |
| x→2 |
| 4 |
| x2-4 |
| 1 |
| x-2 |
| A、-1 | ||
B、-
| ||
C、
| ||
| D、1 |
分析:先进行通分,然后消除零因子,可以把
(
-
)简化为
,由此可得答案.
| lim |
| x→2 |
| 4 |
| x2-4 |
| 1 |
| x-2 |
| lim |
| x→2 |
| -1 |
| x+2 |
解答:解:
(
-
)=
=
=-
,
故选B.
| lim |
| x→2 |
| 4 |
| x2-4 |
| 1 |
| x-2 |
| lim |
| x→2 |
| 2-x |
| (x2-4) |
| lim |
| x→2 |
| -1 |
| x+2 |
| 1 |
| 4 |
故选B.
点评:本题考查函数的极限,解题时要注意消除零因子.
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