We have,
x,y,z are in an A.P.
Then,
y=x+z2
2y=x+z
Let f(x)=x+y2y−x+y+z2y−z
Therefore,
f(x)=x+x+z2x+z−x+x+z2+zx+z−z
⇒3x+z2z+x+3z2x
⇒12(3x2+xz+xz+3z2xz)
⇒12(3x2+3z2+2xzxz)
Hence, this is the answer
If three positive real numbers x, y, z satisfy y - x = z - y and xyz = 4, then what is the minimum possible value of y ?