Deriv moebius
deriv_moebius
Plain-language statement
Derivative of the Möbius transformation: d/dz[(az+b)/(cz+d)] = 1/(cz+d)². Uses det(γ) = 1: a(cz+d) - c(az+b) = ad - bc = 1.
Source project: Sphere Packing in Dimension 8
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