My Trigonometry paclet for The Wolfram Paclet Repository. ^{(published docs)(bleeding-edge docs)}

Trigonometry extends the built-in Wolfram Language trigonometry functionality by providing definitions for over 50 functions not currently included in the system. We all know about sin, cos, and tan. Some of us may even know about sec, arcsin, cosh, and arctanh. A considerably smaller but still not-nonexistent group may know of Haversine and InverseHaversin. But...have you ever heard of Covercosine, Excosecant, and Chord?! Well if not, then this paclet is for you! This Paclet gathers a dozen little-used circular trig functions, their hyperbolic analogues, and the inverses of all of these, into a single, easy-to-use collection that works seamlessly with the 6,000+ Wolfram Language functions.

• Consider changing earlier documentation (e.g. Versine) to say "...is defined in terms of..." instead of immediately going with "...can be represented in terms of..." to mimic the way that Inverse* documentation is phrased.
• Add in historical examples of why people ever studied these functions (i.e. Google versine and see mapping, etc., uses that can be copied over).
• Also add in some of the trig identities mentioned in various Wiki pages, etc.
• Consider mentioning various abbreviations, etc. for the functions
• Fill in the doc pages for the hyperbolic functions and their inverses.
• Continue honing main page shingle info, examples, etc.
• Check the Future'd documentation blocks and try to do the math to figure out more complex relationships between functions. This should particularly relate circular functions with imaginary arguments to their hyperbolic analogues.
• Include cis(z)? link
• Include various definitions of so-called parabolic trig functions.
• Maybe later in Tech Note, consider incorporating some of the below-mentioned juicy trig-related tidbits when the time is right.
• Consider best implementation of CoVerHa as shown in image. Also, Ex, including $tan$ in some functions, etc.
• Also include other juicy trig-related tidbits that prove useful!