IMO Shortlist 1991 problem 2
Kvaliteta:
Avg: 0,0Težina:
Avg: 0,0 is an acute-angled triangle. is the midpoint of and is the point on such that . is the foot of the perpendicular from to . The lines through perpendicular to , meet respectively at . Show that is tangent to the circle through at .
Original Formulation:
For an acute triangle is the midpoint of the segment is a point on the segment such that is the foot of the perpendicular line from to is the point of intersection of segment and the line passing through that is perpendicular to and finally, is the point of intersection of the segment and the line passing through that is perpendicular to Show that the circumcircle of is tangent to the side at point
Original Formulation:
For an acute triangle is the midpoint of the segment is a point on the segment such that is the foot of the perpendicular line from to is the point of intersection of segment and the line passing through that is perpendicular to and finally, is the point of intersection of the segment and the line passing through that is perpendicular to Show that the circumcircle of is tangent to the side at point
Izvor: Međunarodna matematička olimpijada, shortlist 1991