If a, b, c are in GP, prove that a3, b3, c3 are in GP
To prove: a3, b3, c3 are in GP
Given: a, b, c are in GP
Proof: As a, b, c are in GP
⇒ b2 = ac
Cubing both sides
= common ratio = r
From the above equation, we can say that a3, b3, c3 are in GP