\(ABCD\) is cyclic. The feet of the perpendicular from \(D\) to the lines \(AB, BC, CA\) are \(P, Q, R\) respectively. Show that the angle bisectors of \(ABC\) and \(CDA\) meet on the line \(AC\) iff \(RP = RQ\).
| Attributes | Олімпіадна |
|---|---|
| Source | International Mathematical Olympiad |
| Year | 2004 |
| Number | 4 |
| Difficulty | 10.0 |
| Themes | Геометрія |