x | ( | x | − | 1 | ) | ( | x | − | 9 20 | ) | = | 0 |
方程左边 = | x | x | ( | x | − | 9 20 | ) | − | x | × | 1 | ( | x | − | 9 20 | ) |
= | x | x | x | − | x | x | × | 9 20 | − | x | × | 1 | ( | x | − | 9 20 | ) |
= | x | x | x | − | x | x | × | 9 20 | − | x | × | 1 | x | + | x | × | 1 | × | 9 20 |
= | x | x | x | − | x | x | × | 9 20 | − | x | × | 1 | x | + | x | × | 9 20 |
x | x | x | − | x | x | × | 9 20 | − | x | × | 1 | x | + | 9 20 | x | = | 0 |
x2= | 9 20 |
x3=1 |