IMO 1987 LL FRA16

Let ABC be a triangle. For every point M belonging to segment

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IMO 1987 LL FRA16

Origin: FRA

Problem

Let ABC be a triangle. For every point M belonging to segment BC we denote by B′ and c′ the orthogonal projections of M on the straight lines AC and BC. Find points M for which the length of segment B′C′ is a minimum.