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If in the expansion of ( (2^x+ 1 4^x )^n, T₃=7 T₂ ) and sum of the binomial coefficients of second and third terms is 36 , then the value of (x ) is -

Options

  1. A(-1 / 3 )
  2. B(-1 / 2 )
  3. C(1 / 3 )
  4. D(1 / 2 )

Correct answer

A. (-1 / 3 )

Step-by-step solution

( aligned & ^n C₁+ ^n C₂=36 n=8 & T₃=7 ~T ₂ (2^ x )^3=1 / 2 & 3 x =-1 x =- 1 3 aligned )

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