| s | ( | s | + | 2 | ) | ( | s | + | 3 | ) | = | ( | s | + | 5 | ) | ( | ( | s | + | 2 | ) | ( | s | + | 3 | ) | + | s | ( | s | + | 2 | ) | + | s | ( | s | + | 3 | ) | ) |
| 方程左边 = | s | s | ( | s | + | 3 | ) | + | s | × | 2 | ( | s | + | 3 | ) |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | ( | s | + | 3 | ) |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | s | × | 2 | × | 3 |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | s | × | 6 |
| s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 6 | s | = | ( | s | + | 5 | ) | ( | ( | s | + | 2 | ) | ( | s | + | 3 | ) | + | s | ( | s | + | 2 | ) | + | s | ( | s | + | 3 | ) | ) |
| 方程右边 = | s | ( | ( | s | + | 2 | ) | ( | s | + | 3 | ) | + | s | ( | s | + | 2 | ) | + | s | ( | s | + | 3 | ) | ) | + | 5 | ( | ( | s | + | 2 | ) | ( | s | + | 3 | ) | + | s | ( | s | + | 2 | ) | + | s | ( | s | + | 3 | ) | ) |
| = | s | ( | s | + | 2 | ) | ( | s | + | 3 | ) | + | s | s | ( | s | + | 2 | ) | + | s | s | ( | s | + | 3 | ) | + | 5 | ( | ( | s | + | 2 | ) | ( | s | + | 3 | ) | + | s | ( | s | + | 2 | ) | + | s | ( | s | + | 3 | ) | ) |
| = | s | s | ( | s | + | 3 | ) | + | s | × | 2 | ( | s | + | 3 | ) | + | s | s | ( | s | + | 2 | ) | + | s | s | ( | s | + | 3 | ) |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | ( | s | + | 3 | ) | + | s | s | ( | s | + | 2 | ) |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | s | × | 2 | × | 3 |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | s | × | 6 | + | s |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 6 | s | + | s |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 6 | s | + | s |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 6 | s | + | s |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 6 | s | + | s |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 6 | s | + | s |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 6 | s | + | s |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 6 | s | + | s |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 21 | s | + | s |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 21 | s | + | s |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 21 | s | + | s |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 31 | s | + | s |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 31 | s | + | s |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 31 | s | + | s |
| = | s | s | s | + | s | s | × | 3 | + | s | × | 2 | s | + | 41 | s | + | s |