Babylonian square root

Compute √a like a #Babylonian….

1) Make a guess x₀ > 0 for √a

2) The average x₁ = ½ (x₀ +a/x₀) is closer to √a than either x₀ or a/x₀

3) Iterating step 2 gives you a sequence x₁, x₂, x₃, … that converges to √a .

From FB