If a, b, c are in G.P., then prove that :

As a,b,c are in GP


Note:


1. In general, the GP series is like a,ar,ar2……….


2. In this, b = ar and c = br = ar2


So we proceed forward with the aim to equalize LHS and RHS of the equation to be proved using the above ideas.


L.H.S =


LHS =


LHS =


Now


R.H.S =


RHS =


RHS = 1/r


Clearly we observed that,


LHS = RHS = (1/r) …Proved


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