| ( | 2000 | ( | 1 | + | X | ) | − | 1000 | ) | ( | 1 | + | X | ) | = | 4285 4 |
| 方程左边 = | 2000 | ( | 1 | + | X | ) | ( | 1 | + | X | ) | − | 1000 | ( | 1 | + | X | ) |
| = | 2000 | × | 1 | ( | 1 | + | X | ) | + | 2000 | X | ( | 1 | + | X | ) | − | 1000 | ( | 1 | + | X | ) |
| = | 2000 | ( | 1 | + | X | ) | + | 2000 | X | ( | 1 | + | X | ) | − | 1000 | ( | 1 | + | X | ) |
| = | 2000 | × | 1 | + | 2000 | X | + | 2000 | X | ( | 1 | + | X | ) | − | 1000 | ( | 1 | + | X | ) |
| = | 2000 | + | 2000 | X | + | 2000 | X | ( | 1 | + | X | ) | − | 1000 | ( | 1 | + | X | ) |
| = | 2000 | + | 2000 | X | + | 2000 | X | × | 1 | + | 2000 | X | X | − | 1000 | ( | 1 | + | X | ) |
| = | 2000 | + | 2000 | X | + | 2000 | X | + | 2000 | X | X | − | 1000 | ( | 1 | + | X | ) |
| = | 2000 | + | 4000 | X | + | 2000 | X | X | − | 1000 | ( | 1 | + | X | ) |
| = | 2000 | + | 4000 | X | + | 2000 | X | X | − | 1000 | × | 1 | − | 1000 | X |
| = | 2000 | + | 4000 | X | + | 2000 | X | X | − | 1000 | − | 1000 | X |
| = | 1000 | + | 3000 | X | + | 2000 | X | X |
| 1000 | + | 3000 | X | + | 2000 | X | X | = | 4285 4 |