| a+9b |
| 3ab |
| a+3b |
| 3ab |
| x4-1 |
| (x-1)4 |
| 1 |
| x-1 |
| 1 |
| x+1 |
| mn |
| m-n |
| 4 |
| n-m |
| x-3 |
| nx-4 |
| 5 |
| x-n |
| 1 |
| x-3 |
| 6 |
| x2-9 |
| x2-2xy+y2 |
| y |
| x2-y2 |
| x2y |
| 2a |
| a2-4 |
| 1 |
| a-2 |
| 3-x |
| 2x-4 |
| 5 |
| x-2 |
| x2-4x+4 |
| x2-2x+1 |
| x-1 |
| x2-4 |
| x-2 |
| 2x+x2 |
| 1 |
| a+2 |
| a2+2a+1 |
| a2-4 |
| b |
| a2 |
| b |
| a |
| a |
| a-b |
| b |
| b-a |
| y-3 |
| 4y-8 |
| 5 |
| y-2 |
| 1 |
| x-1 |
| 1 |
| x+1 |
| 3 |
| x |
| x2-9 |
| x |
| x2 |
| x2-4 |
| 2+x |
| x2-2x |
| 1 |
| x-2 |
| a+b |
| 2 |