MathDB

65

Part of 1992 IMO Longlists

Problems(1)

Points in the space - IMO LongList 1992 SAF1

Source:

9/2/2010
If A,B,CA, B, C, and DD are four distinct points in space, prove that there is a plane PP on which the orthogonal projections of A,B,CA, B, C, and DD form a parallelogram (possibly degenerate).
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