( | 3 | a | − | 3 | ) | ( | 1 | + | ( | 1 | ÷ | 3 | ) | a | ) | = | 2 | a |
方程左边 = | 3 | a | ( | 1 | + | ( | 1 | ÷ | 3 | ) | a | ) | − | 3 | ( | 1 | + | ( | 1 | ÷ | 3 | ) | a | ) |
= | 3 | a | × | 1 | + | 3 | a | ( | 1 | ÷ | 3 | ) | a | − | 3 | ( | 1 | + | ( | 1 | ÷ | 3 | ) | a | ) |
= | 3 | a | + | 3 | a | ( | 1 | ÷ | 3 | ) | a | − | 3 | ( | 1 | + | ( | 1 | ÷ | 3 | ) | a | ) |
= | 3 | a | + | 3 | a | × | 1 | ÷ | 3 | × | a | − | 3 | ( | 1 | + | ( | 1 | ÷ | 3 | ) | a | ) |
= | 3 | a | + | 1 | a | a | − | 3 | ( | 1 | + | ( | 1 | ÷ | 3 | ) | a | ) |
= | 3 | a | + | 1 | a | a | − | 3 | × | 1 | − | 3 | ( | 1 | ÷ | 3 | ) | a |
= | 3 | a | + | 1 | a | a | − | 3 | − | 3 | ( | 1 | ÷ | 3 | ) | a |
= | 3 | a | + | 1 | a | a | − | 3 | − | 3 | × | 1 | ÷ | 3 | × | a |
= | 3 | a | + | 1 | a | a | − | 3 | − | 1 | a |
= | 2 | a | + | 1 | a | a | − | 3 |
2 | a | + | 1 | a | a | − | 3 | = | 2 | a |