If the (a+1)th ,7th ,and (b+1)th terms of an A.P, are in G.P with a,6,b being in H.P, then the 4th term of this A.P is ? (A) -7/2 (B) 7/2 (C) 0 (D) 3
For the AP in Question, suppose the
the common difference are , resp.,
Solving these for
But, in that event,
So, let us discard that possibility.
We are now left with
Hence, the Right Option is (C) 0.