| 128 | ÷ | ( | x | + | 1 | ) | = | 2 | ( | x | + | 1 | ) |
| 方程两边同时乘以: | ( | x | + | 1 | ) |
| 128 | = | 2 | ( | x | + | 1 | ) | ( | x | + | 1 | ) |
| 128 | = | 2 | x | ( | x | + | 1 | ) | + | 2 | × | 1 | ( | x | + | 1 | ) |
| 128 | = | 2 | x | ( | x | + | 1 | ) | + | 2 | ( | x | + | 1 | ) |
| 128 | = | 2 | x | x | + | 2 | x | × | 1 | + | 2 | ( | x | + | 1 | ) |
| 128 | = | 2 | x | x | + | 2 | x | + | 2 | ( | x | + | 1 | ) |
| 128 | = | 2 | x | x | + | 2 | x | + | 2 | x | + | 2 | × | 1 |
| 128 | = | 2 | x | x | + | 2 | x | + | 2 | x | + | 2 |
| 128 | = | 2 | x | x | + | 4 | x | + | 2 |