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Cosines everywhere (Posted on 2005-03-21)

Prove that in any triangle ABC, 8.cos(A).cos(B).cos(C) < 1.

See The Solution Submitted by Federico Kereki

Rating: 4.5000 (2 votes)

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This problem needs some formatting changes...

| Comment 2 of 6 |

The way it comes across on my web browser (IE 5.50 on Win '98) I can not understand what the problem is asking.

What does 8.cos(A).cos(B).cos(C) mean?

Are the periods supposed to be multiplication signs?

Posted by Erik O. on 2005-03-22 17:25:46

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