| ( | x | + | 1 1000000000 | ) | ( | x | + | 1 10000000 | ) | − | 1 100000000000000 | = | 0 |
| 方程左边 = | x | ( | x | + | 1 10000000 | ) | + | 1 1000000000 | ( | x | + | 1 10000000 | ) | − | 1 100000000000000 |
| = | x | x | + | x | × | 1 10000000 | + | 1 1000000000 | ( | x | + | 1 10000000 | ) | − | 1 100000000000000 |
| = | x | x | + | 1 10000000 | x | + | 1 1000000000 | x | + | 1 1000000000 | × | 1 10000000 | − | 1 100000000000000 |