| x |
| x+1 |
| 3x2 |
| 1−x2 |
| 1 |
| x−1 |
=
| x+x+1 |
| x+1 |
| 1−x2−3x2 |
| 1−x2 |
| 1 |
| x−1 |
=
| 2x+1 |
| x+1 |
| (1+2x)(1−2x) |
| (1+x)(1−x) |
| 1 |
| x−1 |
=
| 1−x |
| 1−2x |
| 1 |
| x−1 |
=
| 1 |
| 2x−1 |
当x=0，则原式=-1．
| x |
| x+1 |
| 3x2 |
| 1−x2 |
| 1 |
| x−1 |
| x |
| x+1 |
| 3x2 |
| 1−x2 |
| 1 |
| x−1 |
| x+x+1 |
| x+1 |
| 1−x2−3x2 |
| 1−x2 |
| 1 |
| x−1 |
| 2x+1 |
| x+1 |
| (1+2x)(1−2x) |
| (1+x)(1−x) |
| 1 |
| x−1 |
| 1−x |
| 1−2x |
| 1 |
| x−1 |
| 1 |
| 2x−1 |