| Positive roots in case | |||||||
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( ): Case |
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| Changes of sign | Number of positive roots |
| 1 | − | + | + | + | + | 1 | 1 |
| 2 | − | + | + | + | + | 1 | 1 |
| 3 | − | − | − | + | + | 1 | 1 |
| 4 | − | − | − | − | + | 1 | 1 |
| 5 | − | + | + | − | + | 3 | 1, 3 |
| 6 | − | + | − | + | + | 3 | 1, 3 |
| 7 | − | + | − | − | + | 3 | 1, 3 |
| 8 | − | − | + | − | + | 3 | 1, 3 |