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If (x-y), x and (x+y) are in H.P., then x y 2 =

Options

  1. A2
  2. B2
  3. C- 2
  4. D-2

Correct answer

C. - 2

Step-by-step solution

array ll x= 2 (x-y) (x+y) (x-y)+ (x+y) = 2 ( ^2 x- ^2 y ) 2 x y ^2 x y= ^2 x- ^2 y & ^2 x(1- y)= ^2 y ^2 x 2 ^2 y 2 =4 ^2 y 2 ^2 y 2 ; & ^2 x ^2 y 2 =2 x y 2 = 2 array

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