See here: https://github.com/jkabrg/Spherical-law-of-cosines-proof-using-Sympy-and-quaternions/blob/master/derivation.ipynb https://github.com/jkabrg/Spherical-

See here: https://github.com/jkabrg/Spherical-law-of-cosines-proof-using-Sympy-and-quaternions/blob/master/derivation.ipynb https://github.com/jkabrg/Spherical-law-of-cosines-proof-usi... I'll provide more explanation later.