If the positive
real numbers a, b and c are in Arithmetic Progression, such that abc = 4, then
minimum possible value of b is:

(A)
2

^{3/2}
(B)
2

^{2/3}
(C)
2

(D)None of the above^{1/3}**Solution follows here:****Solution:**
Given that a,b,c
are in A.P. ∴ b = (a+c)/2 ----
(1)

And also given that, abc =4 => b = 4/ac ---- (2)

From (1) and (2),

(a+c)/2 = 4/ac
=> (a+c)ac = 8 ----
(3)

For b to be minimum in A.P, a=c ----
(4)

From (3) and (4),

(2a)a

^{2}= 8 => a^{3}= 4 => a = 4^{1/3 }
From (1) and (4), b = 2a/2 = a = 4

^{1/3}= 2^{2/3}**Answer(B)**
super logic

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