2. Seva theorem

3. Ptolemy theorem

4. siemsen theorem

5. Stewart Theorem

6. Cross ratio theorem

7. Apolloni Circle

8. Nine o'clock circle

9. Euler line

65438+

1 1. Newton line

12. This has no name: if three circles intersect and the center of the circle is not a * * * line, then the straight line where the three male * * * chords are located is the * * * point (intersection point).

13. Cauchy inequality

14. Vector inequality

. . . Why don't you go to the encyclopedia? You can't remember that much. .