Julia Sets and the Mandelbrot Set

Real Newton's Method

Newton's method for approximating the roots of a function
Newton's method becomes interesting for functions with multiple roots. Then a natural question is which initial guesses x0 will iterate to which root? For a given root, the collection of all such guesses is called the basin of attraction of that root. Here is a simple example.
We can reformulate Newton's method using graphical iteration.
With graphical iteration, finding the basins of attraction is straightforward.
For some functions, the basins of attraction are intricately interwound, so much that they possess the Wada property.
Finally, we can find initial guesses for which Newton's method fails to converge to any root. Analyzing these failures reveals a familiar shape.

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