# Hyperbolic Functions

1. Jan 3, 2005

### mathemagician

Hi! How do you write the LaTeX code for the secant, cosecant, and cotangent hyperbolic functions?

I tried using \sech, \csch, and \coth but I am getting an error when I run the latex program. It is giving me a undefiend control sequence message? Is there a package I need to include in my .tex file to have those hyperbolic functions?

Thanks

2. Jan 3, 2005

### matt grime

just use \text{sech} and so on. you could create your own macro too. these aren't latex commands you see, though the coth one is supposed to be.

rather than search for a package that may have them and probably won't install easily just create the macros in your preamble

3. Jan 3, 2005

### mathemagician

Thanks. I think I sort of jumped to conclusions with the coth. However, I still get an undefined control sequence error using \text{}. Does it matter it being used within an {eqnarray*} ?

4. Jan 3, 2005

### krab

$\coth x$ works for me... I'm not using \text. Maybe you left no space between coth and the argument...

5. Jan 4, 2005

### matt grime

as he says, he's got coth to work.

i don't know why it's not working in an eqnarray* (though I wouldn't put the braces there ). Some environments have problems if \ is the first character of an entry in some slot, you could try typing {\text{sech}}

6. Mar 10, 2010

The other way around this problem, especially if using the command several times, is to create a new command in the preamble.

\newcommand{\sech}{\mathrm{sech} \,}

And similar for the others. The \mathrm will ensure it's written in normal font and the \, will make sure there is a gap between the function and variable.