| ( | 48 | ( | 1 | − | x | ) | ) | ( | 1 | − | x | ) | = | 0 |
| 方程左边 = | 48 | ( | 1 | − | x | ) | ( | 1 | − | x | ) |
| = | 48 | × | 1 | ( | 1 | − | x | ) | − | 48 | x | ( | 1 | − | x | ) |
| = | 48 | ( | 1 | − | x | ) | − | 48 | x | ( | 1 | − | x | ) |
| = | 48 | × | 1 | − | 48 | x | − | 48 | x | ( | 1 | − | x | ) |
| = | 48 | − | 48 | x | − | 48 | x | ( | 1 | − | x | ) |
| = | 48 | − | 48 | x | − | 48 | x | × | 1 | + | 48 | x | x |
| = | 48 | − | 48 | x | − | 48 | x | + | 48 | x | x |
| = | 48 | − | 96 | x | + | 48 | x | x |
| 48 | − | 96 | x | + | 48 | x | x | = | 0 |