Answer:
x₁ = 3,29296875
x₂ = 3,276659786
x₃ = 3,279420685
Explanation:
This is a recurrent relationship between xₙ₊₁ and xₙ
To get x₁, write the formula with n=0:
Then fill in what you know, x₀=3.2. This gives you x₁.
Repeat for n=1,... and so forth.
Excel can do this effectively, see picture.