Extended Trig Methods

[RhoSigma]

And some of those where wrong, as discussed and patched here: https://qb64phoenix.com/forum/showthread.php?tid=2125

I don't know if the wiki was ever corrected, or not.  Someone will need to check that soon.  

Indeed, there are a  couple math keywords without a dedicated wiki page yet. Those should have been added by the one who actually implemented the keywords into the language and hence knows best how they work. However, I've no idea who was it, my best guess either of @luke, @FellippeHeitor or @SMcNeill .

_ARCCOT, _ARCCSC, _ARCSEC, _COT, _COTH, _COSH, _CSC, _CSCH, _SEC, _SECH, _SINH, _TANH

In alternative anybody who's familiar with this kind of math could take the task, just let me know if you need a wiki account. Wish my Dad would still be alive, as math teacher he could explain all this to the best, unfortunately I did not inherit much of his math talents