If a be the A.M. and x, y be the two G.M.'s between b and c, show that
Since a is the A.M. between b and c
∴ ...(i)
Since x, y are two G.M.'s between b and c
∴ b, x, y, c are in G.P.
Let r be the common ratio
L.H.S. =
= bc (b + c) = bc(2a) {By using (i)}
= 2abc = R.H.S.
The product of three numbers in G.P. is 125 and the sum of their products taken in pairs is Find them.
The sum of three numbers in G.P. is 21 and the sum of their squares is 189. Find the numbers.