Positive roots in case | |||||||
( ): Case |
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| Changes of sign | Number of positive roots |
1 | + | + | + | + | + | 0 | 0 |
2 | + | + | + | + | + | 2 | 0, 2 |
3 | + | − | − | + | + | 2 | 0, 2 |
4 | + | − | − | − | + | 2 | 0, 2 |
5 | + | + | + | − | + | 2 | 0, 2 |
6 | + | + | − | + | + | 2 | 0, 2 |
7 | + | + | − | − | + | 2 | 0, 2 |
8 | + | − | + | − | + | 4 | 0, 2, 4 |