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99 Percentile Qs Bank for JEE MainMathematicsSequences and Series

and lie in Q₃ . If ( - ), , ( + ) are in harmonic progression, then 2 =

Options

  1. A- 2
  2. B2
  3. C- 3
  4. D3

Correct answer

B. 2

Step-by-step solution

Given, ( - ), , ( + ) are in HP array lc & 2 = 1 ( - ) + 1 ( + ) & 2 = ( + )+ ( - ) ( - ) ( + ) & 2 = 2 ^2 - ^2 & ^2 - ^2 = ^2 & ^2 (1- )= ^2 & ^2 = 1- 2 1- ^2 =1+ & ^2 =2 ^2 2 / 2= 2 array

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