What are some good books to learn spherical trigonometry from basics to the advanced level?
As far as I know, the bibliography on this subject is mostly old. One good book is 'Spherical Trigonometry: "For the Use of Colleges and Schools" ' by I.Todhunter. There is also this one that has entered the public domain as its copyright has expired so it is available by Google.
As an aside, one good book that I've read that is about Spherical Astronomy - including one chapter of Spherical Trigonometry, is W.M.Smart's "Textbook on Spherical Astronomy" in case you're interested for spherical trigonometry in the context of Astronomy.
Gutenberg project has TeXed up version of I.Todhunter's book http://www.gutenberg.org/files/1977...n_id=dac72e51d0dc3808c216536dba2bbb5626215aa7.
I've read Heavenly Mathematics: The Forgotten Art of Spherical Trigonometry by Glen Van Brummelen. I found it to be good. It's a blend of history text and mathematics instruction.
Thanks everyone for the recommendations. I'll surely check then out.
A. A. Klaf, Dover.
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