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If a₁, a₂, , a_n are in H.P., then the expression a₁ a₂+a₂ a₃+ +a_ n-1 a_n is equal to

Options

  1. An (a₁-a_n )
  2. B(n-1) (a₁-a_n )
  3. Cn a₁ a_n
  4. D(n-1) a₁ a_n

Correct answer

D. (n-1) a₁ a_n

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