| 2 | x | ( | x | − | 1 | ) | = | ( | 1 | + | x | ) | ( | 1 | − | x | ) |
| 方程左边 = | 2 | x | x | − | 2 | x | × | 1 |
| = | 2 | x | x | − | 2 | x |
| 2 | x | x | − | 2 | x | = | ( | 1 | + | x | ) | ( | 1 | − | x | ) |
| 方程右边 = | 1 | ( | 1 | − | x | ) | + | x | ( | 1 | − | x | ) |
| = | 1 | × | 1 | − | 1 | x | + | x | ( | 1 | − | x | ) |
| = | 1 | − | 1 | x | + | x | ( | 1 | − | x | ) |
| = | 1 | − | 1 | x | + | x | × | 1 | − | x | x |
| = | 1 | − | 0 | x | − | x | x |
| 2 | x | x | − | 2 | x | = | 1 | − | 0 | x | − | x | x |
| x1= | - | 1 3 |
| x2=1 |