| x-y |
| x |
| 2xy-y2 |
| x |
| x2-4 |
| x2-4x+4 |
| x2-x |
| x-1 |
| 3 |
| 2 |
| 1 |
| a+b |
| 1 |
| a-b |
| 2 |
| 3 |
| 2 |
| 3 |
| 3 |
| 8 |
| 3 |
| 8 |
| 4 |
| 15 |
| 4 |
| 15 |
| a |
| b |
| a |
| b |
| a2 |
| a-b |
| b2 |
| b-a |
| a+b |
| ab |
| x2-1 |
| x2-2x+1 |
| x2-2x |
| x-2 |
| a-b |
| a |
| ah-hab+bh |
| a |
| 2x |
| x-3 |
| x |
| x+3 |
| x |
| x2-9 |
| 3 |
| 15 |
| x-1 |
| x-4 |
| x-1 |
| 10 |
| a2+3a-4 |
| a+1 |
| a-1 |
| 4ab |
| a-b |
| 4ab |
| a+b |
| 3-x |
| 2x-4 |
| 5 |
| x-2 |
| a-b |
| a+b |
| a2+b2 |
| a2-b2 |
| a+b |
| ab |
| a2b+ab2 |
| a2+b2 |
| 17 |
| 4 |
| 1 |
| 1+1 |
| 1 |
| 12-1 |