Members of geometric progression and geometric average
$$b_{n} = \sqrt {b_{M1}\cdot b_{P1}}$$
b_n - n-th member
b_M1 - (n-1)-th member
b_P1 - (n+1)-th member
b_M1 - (n-1)-th member
b_P1 - (n+1)-th member
Find
It is known that:
= 