If a, b, c, d are in GP, then prove that
are in GP
To prove: are in GP.
Given: a, b, c, d are in GP
Proof: When a,b,c,d are in GP then
From the above, we can have the following conclusion
⇒ bc = ad … (i)
⇒ b2 = ac … (ii)
⇒ c2 = bd … (iii)
Considering
=
=
From eqn. (i) , (ii) and (iii)
=
=
=
From the above equation, we can say that are in GP.