| ( | 2 | − | x | ) | ( | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 4 | ) | = | 0 |
| 方程左边 = | 2 | ( | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 4 | ) | − | x | ( | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 4 | ) |
| = | 2 | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 2 | × | 4 | − | x | ( | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 4 | ) |
| = | 2 | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 8 | − | x | ( | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 4 | ) |
| = | - | 2 | × | 2 | ( | 3 | − | x | ) | − | 2 | x | ( | 3 | − | x | ) | + | 8 | − | x | ( | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 4 | ) |
| = | - | 4 | ( | 3 | − | x | ) | − | 2 | x | ( | 3 | − | x | ) | + | 8 | − | x | ( | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 4 | ) |
| = | - | 4 | × | 3 | + | 4 | x | − | 2 | x | ( | 3 | − | x | ) | + | 8 | − | x | ( | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 4 | ) |
| = | - | 12 | + | 4 | x | − | 2 | x | ( | 3 | − | x | ) | + | 8 | − | x | ( | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 4 | ) |
| = | - | 4 | + | 4 | x | − | 2 | x | ( | 3 | − | x | ) | − | x | ( | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 4 | ) |
| = | - | 4 | + | 4 | x | − | 2 | x | × | 3 | + | 2 | x | x | − | x | ( | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 4 | ) |
| = | - | 4 | + | 4 | x | − | 6 | x | + | 2 | x | x | − | x | ( | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 4 | ) |
| = | - | 4 | − | 2 | x | + | 2 | x | x | − | x | ( | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | + | 4 | ) |
| = | - | 4 | − | 2 | x | + | 2 | x | x | − | x | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) | − | x | × | 4 |
| = | - | 4 | − | 6 | x | + | 2 | x | x | − | x | ( | - | 2 | − | x | ) | ( | 3 | − | x | ) |
| = | - | 4 | − | 6 | x | + | 2 | x | x | + | x | × | 2 | ( | 3 | − | x | ) | + | x | x | ( | 3 | − | x | ) |
| = | - | 4 | − | 6 | x | + | 2 | x | x | + | x | × | 2 | × | 3 | − | x | × | 2 | x |
| = | - | 4 | − | 6 | x | + | 2 | x | x | + | x | × | 6 | − | x | × | 2 | x | + | x |
| = | - | 4 | − | 0 | x | + | 2 | x | x | − | x | × | 2 | x | + | x | x | ( | 3 | − | x | ) |
| = | - | 4 | + | 2 | x | x | − | x | × | 2 | x | + | x | x | × | 3 | − | x | x |
| - | 4 | + | 2 | x | x | − | x | × | 2 | x | + | x | x | × | 3 | − | x | x | = | 0 |