| 8 | x | ( | - | 4 | x | + | 1 | ) | × | 2 | + | 4 | ( | - | 4 | x | + | 1 | ) | × | 2 | + | 2 | ( | - | 4 | x | + | 1 | ) | = | 0 |
| 方程左边 = | 16 | x | ( | - | 4 | x | + | 1 | ) | + | 8 | ( | - | 4 | x | + | 1 | ) | + | 2 | ( | - | 4 | x | + | 1 | ) |
| 16 | x | ( | - | 4 | x | + | 1 | ) | + | 8 | ( | - | 4 | x | + | 1 | ) | + | 2 | ( | - | 4 | x | + | 1 | ) | = | 0 |
| 方程左边 = | - | 16 | x | × | 4 | x | + | 16 | x | × | 1 | + | 8 | ( | - | 4 | x | + | 1 | ) | + | 2 | ( | - | 4 | x | + | 1 | ) |
| = | - | 64 | x | x | + | 16 | x | + | 8 | ( | - | 4 | x | + | 1 | ) | + | 2 | ( | - | 4 | x | + | 1 | ) |
| = | - | 64 | x | x | + | 16 | x | − | 8 | × | 4 | x | + | 8 | × | 1 | + | 2 | ( | - | 4 | x | + | 1 | ) |
| = | - | 64 | x | x | + | 16 | x | − | 32 | x | + | 8 | + | 2 | ( | - | 4 | x | + | 1 | ) |
| = | - | 64 | x | x | − | 16 | x | + | 8 | + | 2 | ( | - | 4 | x | + | 1 | ) |
| = | - | 64 | x | x | − | 16 | x | + | 8 | − | 2 | × | 4 | x | + | 2 | × | 1 |
| = | - | 64 | x | x | − | 16 | x | + | 8 | − | 8 | x | + | 2 |
| = | - | 64 | x | x | − | 24 | x | + | 10 |
| - | 64 | x | x | − | 24 | x | + | 10 | = | 0 |
| x1= | - | 5 8 |
| x2= | 1 4 |