Does MathJax really not recognize cosec?

Question

I tried to get the trig function cosec in MathJax, but it comes out as $\cosec$. In contrast, it works perfectly well for sec: $\sec$. Of course, one can always use \operatorname{cosec} as a workaround ($\operatorname{cosec})$; but this seems clumsy. The shorter form csc works: $\csc$. Perhaps the designers of MathJax simply don't like cosec and think that we should all switch to csc.

Answer 1

No, you're right that mathjax doesn't recognize $\cosec(x)$: $\cosec(x)$, but it recognizes $\csc(x)$: $\csc(x)$ for use when you want to denote cosecant(x). It is likely due to the fact that \sin(x), \cos(x), \tan(x), \sec(x), \cot(x) all have three-letter operator-names, and so the choice of operator for cosecant, in mathjax, similarly has a three-letter operator: \csc(x).

Even though one can speak of $\csc(x) = \frac 1{\sin x}$, mathjax does not recognize $\arccsc(x)$: $\arccsc(x)$, though it recognizes $\csc^{-1}(x)$: $\csc^{-1}(x)$. But nor does it recognize $\arcsec$: $\arcsec$, nor $\arccot$: $\arccot$.

But we do have $\arcsin, \arccos, \arctan$: $\arcsin, \arccos, \arctan$.

Now, a work around, if you're needing to use cosecant a lot in one post, is to write \DeclareMathOperator{cosec}{cosec} before needing to use cosec. Then, you can use it as you like, as you expected you could, by writing \cosec(x). I display the results immediately below. You can click on "edit" to see that it does indeed work.

$\DeclareMathOperator{cosec}{cosec}$

$\cosec(x)$