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If 1 b-a + 1 b-c = 1 a + 1 c then a, b, c are in

Options

  1. AAP
  2. BGP
  3. CHP
  4. DNone of the above

Correct answer

C. HP

Step-by-step solution

aligned & Given 1 b-a + 1 b-c = 1 a + 1 c & 1 b-a - 1 c = 1 a - 1 b-c & c-b+a (b-a) c = b-c-a a(b-c) & c-b+a (b-a) c = -(c-b+a) a(b-c) aligned aligned & a(b-c) & =-(b-a) c & a b-a c & =-b c+a c & b(a+c) & =2 a c & b & = 2 a c a+c . aligned Clearly a, b, c are in H.P.

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