| ( | ( | 2 | a | ÷ | 2 | ) | ( | 2 | a | ÷ | 2 | ) | ) | ÷ | ( | 1 2 | − | 1 2 | a | ) | × | ( | 1 2 | − | 1 2 | a | ) | = | 0 |
| Multiply both sides of the equation by: | ( | 1 2 | − | 1 2 | a | ) |
| ( | ( | 2 | a | ÷ | 2 | ) | ( | 2 | a | ÷ | 2 | ) | ) | ( | 1 2 | − | 1 2 | a | ) | = | 0 |
| ( | 2 | a | ÷ | 2 | ) | ( | 2 | a | ÷ | 2 | ) | ( | 1 2 | − | 1 2 | a | ) | = | 0 |
| 2 | a | ÷ | 2 | × | ( | 2 | a | ÷ | 2 | ) | ( | 1 2 | − | 1 2 | a | ) | = | 0 |
| 1 | a | ( | 2 | a | ÷ | 2 | ) | ( | 1 2 | − | 1 2 | a | ) | = | 0 |
| 1 | a | × | 2 | a | ÷ | 2 | × | ( | 1 2 | − | 1 2 | a | ) | = | 0 |
| 1 | a | a | ( | 1 2 | − | 1 2 | a | ) | = | 0 |
| 1 | a | a | × | 1 2 | − | 1 | a | a | × | 1 2 | a | = | 0 |
1 2 | a | a | − | 1 2 | a | a | a | = | 0 |