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Galaxy: Rotations and Dilatations

GeoGebra Script

A = (-1, 0) B = (1, 0) C = (0.68, 0.74) c = Ellipse(A, B, C) a = Slider(0, 1, 0.01, 1, 200, false, true, false, false) Execute(Sequence("A"+k+"="+k+"/2", k, 1, 20)) f(x) = (1 - a) * (x) + a * (-x) Execute(Sequence("B"+k+"=Rotate(Dilate(c, A"+k+", (0, 0)), f(A"+k+" / 4), (0, 0))", k, 1, 20)) Execute(Sequence("ShowLabel(B"+k+", false)", k, 1, 20)) Execute(Sequence("SetDynamicColor(B"+k+", "+k+"/20, 1, 1)", k, 1, 20))

Note

The animation actually shows a variation of colors (HSV) using the expression: 1/"+k+"