If one A.M., A and two geometric means G1 and G2 inserted between any two positive numbers, show that 
Let the numbers be a and b.
Now
or 2A =a+b
Also, G1 and G2 are GM between a and b, then a, G1, G2, b are in G.P.
Let r be the common ratio.
Then, b = ar4–1 = ar3
⇒ ![]()
⇒ ![]()
∴ G1 = ar = ![]()
G2 = ar2 = ![]()
∴ ![]()
a + b = 2A