( | x | − | 2 | ) | ( | x | − | 2 | ) | ( | x | + | 1 | ) | − | 18 | x | − | 20 | = | 0 |
方程左边 = | x | ( | x | − | 2 | ) | ( | x | + | 1 | ) | − | 2 | ( | x | − | 2 | ) | ( | x | + | 1 | ) | − | 18 | x | − | 20 |
= | x | x | ( | x | + | 1 | ) | − | x | × | 2 | ( | x | + | 1 | ) | − | 2 | ( | x | − | 2 | ) | ( | x | + | 1 | ) | − | 18 | x | − | 20 |
= | x | x | x | + | x | x | × | 1 | − | x | × | 2 | ( | x | + | 1 | ) | − | 2 | ( | x | − | 2 | ) | ( | x | + | 1 | ) |
= | x | x | x | + | x | x | × | 1 | − | x | × | 2 | x | − | x | × | 2 | × | 1 |
= | x | x | x | + | x | x | × | 1 | − | x | × | 2 | x | − | x | × | 2 | − | 2 |
= | x | x | x | + | x | x | × | 1 | − | x | × | 2 | x | − | 20 | x | − | 2 |
= | x | x | x | + | x | x | × | 1 | − | x | × | 2 | x | − | 20 | x | − | 2 |
= | x | x | x | + | x | x | × | 1 | − | x | × | 2 | x | − | 20 | x | − | 2 |
= | x | x | x | + | x | x | × | 1 | − | x | × | 2 | x | − | 20 | x | − | 2 |
= | x | x | x | + | x | x | × | 1 | − | x | × | 2 | x | − | 20 | x | − | 2 |
= | x | x | x | + | x | x | × | 1 | − | x | × | 2 | x | − | 22 | x | − | 2 |
= | x | x | x | + | x | x | × | 1 | − | x | × | 2 | x | − | 22 | x | − | 2 |
= | x | x | x | + | x | x | × | 1 | − | x | × | 2 | x | − | 22 | x | − | 2 |
= | x | x | x | + | x | x | × | 1 | − | x | × | 2 | x | − | 18 | x | − | 2 |
x | x | x | + | x | x | × | 1 | − | x | × | 2 | x | − | 18 | x | − | 2 | = | 0 |