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nCr + 2nCr+1 + nCr+2 is equal to (2  less or equal thanless or equal than n)

Maths-General

  1. n+1Cr+1    
  2. none of these    
  3. 2 . nCr+2    
  4. n+2Cr+2    

    Answer:The correct answer is: n+2Cr+2

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