If a, b, c are in G.P., prove that :
As
a, b, c are in G.P, let r be the common ratio.
Therefore,
b = ar … (1)
c = ar2 … (2)
To prove: 
As, LHS = 
⇒ LHS = 
⇒ LHS = 
⇒ LHS = 
As, RHS = 
= LHS
Clearly, LHS = RHS
Hence proved
8
If a, b, c are in G.P., prove that :
As
a, b, c are in G.P, let r be the common ratio.
Therefore,
b = ar … (1)
c = ar2 … (2)
To prove:
As, LHS =
⇒ LHS =
⇒ LHS =
⇒ LHS =
As, RHS = = LHS
Clearly, LHS = RHS
Hence proved