1 20 | ÷ | ( | 1 | + | 1 20 | a | ) | − | 1 10 | ÷ | ( | 1 | + | 1 10 | a | ) | = | 0 |
| 方程两边同时乘以: | ( | 1 | + | 1 20 | a | ) |
1 20 | − | 1 10 | ÷ | ( | 1 | + | 1 10 | a | ) | × | ( | 1 | + | 1 20 | a | ) | = | 0 |
1 20 | − | 1 10 | ÷ | ( | 1 | + | 1 10 | a | ) | × | 1 | − | 1 10 | ÷ | ( | 1 | + | 1 10 | a | ) | × | 1 20 | a | = | 0 |
1 20 | − | 1 10 | ÷ | ( | 1 | + | 1 10 | a | ) | − | 1 200 | ÷ | ( | 1 | + | 1 10 | a | ) | × | a | = | 0 |
| 方程两边同时乘以: | ( | 1 | + | 1 10 | a | ) |
1 20 | ( | 1 | + | 1 10 | a | ) | − | 1 10 | − | 1 200 | a | = | 0 |
1 20 | × | 1 | + | 1 20 | × | 1 10 | a | − | 1 10 | − | 1 200 | a | = | 0 |
1 20 | + | 1 200 | a | − | 1 10 | − | 1 200 | a | = | 0 |
| - | 1 20 | + | 0 | a | = | 0 |
| = | 0 | + | 1 20 |