MathDB

50

Part of 1966 IMO Longlists

Problems(1)

Soviet Union 7

Source: IMO LongList 1959-1966 Problem 50

9/2/2004
For any quadrilateral with the side lengths a,a, b,b, c,c, dd and the area S,S, prove the inequalityS≤a+c2⋅b+d2.S\leq \frac{a+c}{2}\cdot \frac{b+d}{2}.
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