1

Part of 1994 Kurschak Competition

Problems(1)

Parallelogram, maximum of diagonals' angle

Source: Kürschák 1994, problem 1

The ratio of the sides of a parallelogram is

\lambda>1

\lambda

, determine the maximum of the acute angle subtended by the diagonals of the parallelogram.

geometryparallelogramratiogeometry unsolved