MathDB

5

Part of 1968 Polish MO Finals

Problems(1)

any four of b points are vertices of a convex quadrilateral,

Source: Polish MO Finals 1968 p5

8/22/2024
Given n≥4n \ge 4 points in the plane such that any four of them are the vertices of a convex quadrilateral, prove that these points are the vertices of a convex polygon.
geometrypointscombinatoricscombinatorial geometry