题干
若函数f（x）=
，则f（﹣
）+f（﹣
）+f（﹣1）+f（0）+f（1）+f（
）+f（
）=____．
| 2 |
| x |
| + |
| 1 |
| 2 |
| x |
| + |
| 1 |
| 1 |
| 3 |
| 1 |
| 2 |
| 1 |
| 2 |
| 1 |
| 3 |
答案(点此获取答案解析）
7
