( | 4 | n | n | + | 2 | n | ) | ( | 2 | n | − | 1 | ) | ( | 2 | n | − | 2 | ) | = | 140 | ( | n | n | − | n | ) | ( | n | − | 2 | ) |
方程左边 = | 4 | n | n | ( | 2 | n | − | 1 | ) | ( | 2 | n | − | 2 | ) | + | 2 | n | ( | 2 | n | − | 1 | ) | ( | 2 | n | − | 2 | ) |
= | 4 | n | n | × | 2 | n | ( | 2 | n | − | 2 | ) | − | 4 | n | n | × | 1 | ( | 2 | n | − | 2 | ) | + | 2 |
= | 8 | n | n | n | ( | 2 | n | − | 2 | ) | − | 4 | n | n | ( | 2 | n | − | 2 | ) | + | 2 | n | ( | 2 | n | − | 1 | ) |
= | 8 | n | n | n | × | 2 | n | − | 8 | n | n | n | × | 2 | − | 4 |
= | 16 | n | n | n | n | − | 16 | n | n | n | − | 4 | n | n |
= | 16 | n | n | n | n | − | 16 | n | n | n | − | 4 | n | n |
= | 16 | n | n | n | n | − | 16 | n | n | n | − | 8 | n | n |
= | 16 | n | n | n | n | − | 16 | n | n | n | − | 8 | n | n |
= | 16 | n | n | n | n | − | 16 | n | n | n | − | 8 | n | n |
= | 16 | n | n | n | n | − | 16 | n | n | n | − | 8 | n | n |
= | 16 | n | n | n | n | − | 16 | n | n | n | − | 8 | n | n |
= | 16 | n | n | n | n | − | 16 | n | n | n | − | 8 | n | n |
= | 16 | n | n | n | n | − | 16 | n | n | n | − | 8 | n | n |
16 | n | n | n | n | − | 16 | n | n | n | − | 8 | n | n | = | 140 | ( | n | n | − | n | ) | ( | n | − | 2 | ) |
方程右边 = | 140 | n | n | ( | n | − | 2 | ) | − | 140 | n | ( | n | − | 2 | ) |
= | 140 | n | n | n | − | 140 | n | n | × | 2 | − | 140 | n | ( | n | − | 2 | ) |
= | 140 | n | n | n | − | 280 | n | n | − | 140 | n | ( | n | − | 2 | ) |
= | 140 | n | n | n | − | 280 | n | n | − | 140 | n | n | + | 140 | n |
= | 140 | n | n | n | − | 280 | n | n | − | 140 | n | n | + | 280 | n |
16 | n | n | n | n | − | 16 | n | n | n | − | 8 | n | n | = | 140 | n | n | n | − | 280 | n | n | − | 140 | n | n | + | 280 | n |
n4= | 23 4 |