If a, b, c are in GP, prove that a2, b2, c2 are in GP.

To prove: a2, b2, c2 are in GP


Given: a, b, c are in GP


Proof: As a, b, c are in GP


b2 = ac … (i)


Considering b2, c2


= common ratio = r


[From eqn. (i)]


= r


Considering a2, b2


= common ratio = r


[From eqn. (i)]


= r


We can see that in both the cases we have obtained a common ratio.


Hence a2, b2, c2 are in GP.


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