| 1 |
| a |
| 2xy |
| π |
| 3a2b3c |
| 4 |
| 5 |
| 6+x |
| x |
| 7 |
| y |
| 8 |
| 2 |
| x |
| 1 |
| 2 |
| 1 |
| 4 |
| 1 |
| 5+a |
| m+n |
| 5 |
| 1 |
| x |
| a+b |
| 3 |
| 3x |
| 2π |
| a2-b2 |
| a+b |
| 1 |
| 5+m |
| a2 |
| a |
| 1 |
| x |
| 1 |
| 3 |
| x+11 |
| π |
| x2-y2 |
| x+y |
| 1 |
| m |
| 1 |
| a |
| 3 |
| m |
| b |
| 3 |
| c |
| a-b |
| 3 |
| x |
| x-y |
| π |
| 6x |
| π |
| x-1 |
| x |
| 1 |
| 2 |
| 1 |
| a |
| 3 |
| m |
| b |
| 3 |
| c |
| a-b |
| a+b |
| 2b |
| 3 |
| 4 |
| x2+2x+1 |
| 5 |
| m-n |
| m+n |
| 2 |
| x |
| 1 |
| 3 |
| x |
| π-3 |
| 5 |
| a-x |
| x(x+y) |
| x |
| x+3 |
| (x+1)(x-2) |
| 1 |
| x |
| m+n |
| m |
| x-2 |
| x2+1 |
| 1 |
| 3 |
| x+1 |
| π |
| 1 |
| m |
| 图2-2图b+b2 |
| 图-b |
| x2 |
| x |
| x |
| 3 |