Subject: Re: Trigonometric inequality
Date: Mon, 10 Nov 1997 19:08:29 -0700
From: "Francois Begin"

Hi Alex

About a year ago, a young woman posted the following inequality

sin(A)*sin(B)/sin(C/2)^2+sin(A)*sin(C)/sin(B/2)^2+sin(B)*sin(C)/sin(A/2)^2>=9 with A,B,C are the angles of a triangle

Do you know if anybody came up with a proof?

I just looked at it and I find it quite fascinating. I have tried some elementary trigonometric identities on it but with no success so far.

Francois

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