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          Volume 8, Issue 1, Article 29 | 
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             A Method For Establishing Certain Trigonometric Inequalities
 
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          Authors:  | 
          Mowaffaq Hajja,  | 
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          Keywords: 
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          Geometric inequalities, Equifacial tetrahedra, Solid angle. | 
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          Date Received: 
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          07/11/06 | 
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          Date Accepted: 
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          14/02/07 | 
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          Subject Codes: | 
           
             51M16, 52B10. 
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          Editors:  | 
          Peter S. Bullen,   | 
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          Abstract: | 
           
              In this note, we describe a method for establishing trigonometric inequalities that involve symmetric functions in the cosines of the angles of a triangle. The method is based on finding a complete set of relations that define the cosines of such angles.
             
          
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