| 1 |
| 2006×2007 |
| 1 |
| 2007×2008 |
=
| 2006×2008 |
| 2006×2007 |
| 2006×2008 |
| 2007×2008 |
=
| 2008 |
| 2007 |
| 2006 |
| 2007 |
=
| 2008+2006 |
| 2007 |
=
| (2007+1)+(2007−1) |
| 2007 |
=
| 2×2007 |
| 2007 |
=2；
故答案为：2．
| 1 |
| 2006×2007 |
| 1 |
| 2007×2008 |
| 1 |
| 2006×2007 |
| 1 |
| 2007×2008 |
| 2006×2008 |
| 2006×2007 |
| 2006×2008 |
| 2007×2008 |
| 2008 |
| 2007 |
| 2006 |
| 2007 |
| 2008+2006 |
| 2007 |
| (2007+1)+(2007−1) |
| 2007 |
| 2×2007 |
| 2007 |