- John Golden
For examining the fundamental calculation of the Mandelbrot and Julia Sets. The Mandelbrot set is the set of values C for which the function f(z)=z^2+C converges when iterated starting at z=0. a_0=0, a_1=f(0)=C, a_2=f(C)=C^2+C... a_n+1=f(a_n) The Julia set, which can be defined for a broad class of complex functions, has a related idea: keep C constant, a make a set based on the behavior of iterations of a_0=z for different z in the complex plane. This sketch shows you 22 iterations of a_0 = A, and f(z)=z^2 + C, where we think of points (a,b) as representing the complex number a+bi.
More GeoGebra at mathhombre.blogspot.com/p/geogebra.html.