If a, b, c be in AP, b, c, d be in GP and c, d, e be in HP, prove that a, c, e are in GP.
Let a and b be two unequal positive numbers. Then,
A.M. = (a+b)/2 G.M = (ab)
and, H.M. = 2ab/(a+b) To Prove the first part, we have
(A.M.) x (G.M.) = (a+b)/2 x 2ab/(a+b)
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