Finding tangent circles
SMRTR summary
Descartes' theorem reveals an elegant equation for finding two additional circles tangent to three mutually tangent circles. The theorem uses signed curvatures to calculate the radii of the new circles, with one circle fitting between the original three and another surrounding them. A related formula determines the centers of these circles in the complex plane.
SMRTR provides this summary for quick context. The original article belongs to John D. Cook.
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