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If p, q, r are in AP as well as GP, then which one of the following is correct?

Options

  1. Ap=q r
  2. Bp q r
  3. Cp q=r
  4. Dp=q=r

Correct answer

D. p=q=r

Step-by-step solution

aligned & A.P. 2 q=p+r....(1) & G.P. q^2=p r 0= p r & 2 p r =p+r & p+r-2 p r =0 &( p )^2+( r )^2-2 p r =0 &( p - r )^2=0 & p = r & p=r....(2) & 2 q=2 p & q=p....(3) aligned from (2) and (3) p=q=r .

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