I love solving and making recreational math puzzles. My specialties at university were Computer Science and Mathematics.
If you love proving trigonometric identities or if you are preparing for a trigonometry test, check out my TRIGONOMETRIC IDENTITIES WORKBOOK at the Internet Archive. It contains 21 examples of proofs of trigonometric identities and several identities for you to prove.
The workbook is available at:
https://archive.org/details/@will_octagon_gibson
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