According to its tag info, is for questions about

Trigonometric functions (both geometric and circular) . . .

What throws me off is “geometric.”

Which of the following categories of functions would be appropriate for use with if no triangles are actually involved?

1. Circular: $\sin$, $\cos$, $\tan$, $\sec$, $\csc$, $\cot$
2. Inverse circular: $\arcsin$, $\arccos$, $\arctan$, $\operatorname{arcsec}$, $\operatorname{arccsc}$, $\operatorname{arccot}$
3. Hyperbolic: $\sinh$, $\cosh$, $\tanh$, $\operatorname{sech}$, $\operatorname{csch}$, $\coth$
4. Inverse hyperbolic: $\operatorname{arcsinh}$, $\operatorname{arccosh}$, $\operatorname{arctanh}$, $\operatorname{arcsech}$, $\operatorname{arccsch}$, $\operatorname{arccoth}$

When I searched the tags list, neither , nor , appeared, but has posts and a wiki summary, and just has posts.

Could anyone provide guidance about using the aforementioned tags?

• I am probably reading that paragraph differently than you meant it, but you seem to claim both that the tag (hyperbolic-functions) does not exists and that it does exist. You also mention (trigonometric-functions), this tag is one of synonyms of trigonometry tag. (If the clarification of this needs to be a bit longer, feel free to drop me a line in chat.) – Martin Sleziak Oct 6 '17 at 4:46
• I wonder whether it would be reasonable to ping the user who created the tag-excerpt you quote and let them know about this post. (Since this is the user who chose that wording, perhaps they might want to comment on this.) – Martin Sleziak Oct 6 '17 at 4:55
• @MartinSleziak What I mean is that when I go to “tags” beside “questions” and search “hyperbolic,” nothing shows up, but just to be sure, I linked the tag in my post and clicked on it, and voila. Also, I think tagging the creator would be a wonderful idea. – gen-z ready to perish Oct 6 '17 at 5:00
• As you can see from the screenshot I posted in chat (and other links posted there) I had not problem finding the tag. Are you sure you did not search among tags on meta rather than main (or some similar mistake which caused you looking in the wrong place)? – Martin Sleziak Oct 6 '17 at 5:06
• From my recollection of trigonometry, that tag was supposed to encompass both circular and hyperbolic functions. Sometime during my hiatus, somebody then made a tag of hyperbolics, and multiple tagged questions later, we now have the current situation. :P – J. M. isn't a mathematician Oct 7 '17 at 3:02
• @MartinSleziak I think I'd intended "geometric" to mean right-triangle trig, so that "geometric and circular" was intended to encompass trigonometry both as it appears in U.S. secondary school geometry and in U.S. secondary school advanced algebra / algebra 2 / precalculus. I doubt I'd intended to include hyperbolic trig, though probably because I wasn't even thinking about it, not because I intended to exclude it. – Isaac Oct 10 '17 at 20:01
• That is to say, I'd expect the tag to be used for 1 and 2, and I wouldn't have thought about the tag in relation to 3 and 4, but have no immediate objection to its use that way. – Isaac Oct 10 '17 at 20:02