| x | ( | 1 | + | x | ) | ( | 1 | − | x | ) | = | 3 | ÷ | 5 |
| 方程左边 = | x | × | 1 | ( | 1 | − | x | ) | + | x | x | ( | 1 | − | x | ) |
| = | x | × | 1 | × | 1 | − | x | × | 1 | x | + | x | x | ( | 1 | − | x | ) |
| = | x | × | 1 | − | x | × | 1 | x | + | x | x | ( | 1 | − | x | ) |
| = | 1 | x | − | x | × | 1 | x | + | x | x | × | 1 | − | x | x | x |
| 1 | x | − | x | × | 1 | x | + | x | x | × | 1 | − | x | x | x | = | 3 | ÷ | 5 |
| 方程右边 = | 3 5 |
| 1 | x | − | x | × | 1 | x | + | x | x | × | 1 | − | x | x | x | = | 3 5 |