← Lab · Chapter: Recursively defined sequences

Heron's sequence

The iteration \(x_{n+1} = \tfrac12(x_n + a/x_n)\) converging to \(\sqrt a\), drawn as a cobweb: choose \(a\), the starting point and the number of steps. Drag the sliders, or press ▶ to animate. On the graph, pan by dragging with two fingers (or the mouse) and zoom with Shift + mouse wheel.