MathDB

27

Part of 1969 IMO Shortlist

Problems(1)

Restricted existence of cone with axis passing through X

Source:

9/29/2010
(GBR4)(GBR 4) The segment ABAB perpendicularly bisects CDCD at XX. Show that, subject to restrictions, there is a right circular cone whose axis passes through XX and on whose surface lie the points A,B,C,D.A,B,C,D. What are the restrictions?
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