perplexus.info :: Just Math : Quadrilateral Sine Inequality

Quadrilateral Sine Inequality (Posted on 2008-08-05)

Let A,B,C and D be angles in a quadrilateral. Prove that:

√(CSinASinB)+√(ASinCSinD)+√(D|CosACosB|)+√(B|CosCCosD|) ≤ 2√(pi)

No Solution Yet Submitted by Jonathan Lindgren

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re(2): Solution

Comment 3 of 3 |

(In reply to re: Solution by Ady TZIDON)

Quadrilaterals with largest angle greater than 180 are
called concave or re-entrant quadrilaterals.
Check the following link:
http://mathworld.wolfram.com/Quadrilateral.html

Posted by Praneeth on 2008-08-06 08:17:49

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