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Let T_r be the r^ th term of an AP for r=1,2,3, If for some distinct positive integers m and n we have T _ m =1 / n and T _ n =1 / m , then what is T _ mn equal to?

Options

  1. A( mn )⁻¹
  2. Bm ⁻¹+ nn ⁻¹
  3. C1
  4. D0

Correct answer

C. 1

Step-by-step solution

aligned & T _ n = 1 m , ~T _ m = 1 n & 1^ st term = c.d. = 1 m n & ~T _ m n = 1 m n + m n-1 m n =1 aligned

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