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In a triangle ABC, if a : b : c = 7 : 8 : 9, then cos A : cos B equals to

Maths-General

  1. 2 over 9    
  2. 14 over 11    
  3. 22 over 63    
  4. 11 over 63    

    Answer:The correct answer is: 14 over 11

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