# Why can't I use \pi or \equiv in a list?

The problem comes when I try to use a '\' inside an item tag. In my code:

\begin{itemize}
\item   \pi\textsubscript{k}
\item   f\textsubscript{k}(x) \equiv ....
\end{itemize}


both \pi and and \equiv gives me an error.

How can I fix it? I'm new to LaTeX.

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You need the mathematical mode: $\pi$, i.e. use the $...$ as pair around your 'mathematical' command \pi – Christian Hupfer Mar 28 at 15:53

By default the itemize environment will not be in math mode which you need to use \pi or \equiv. Try this:

\begin{itemize}
\item   $\pi_{k}$
\item   $f_k(x) \equiv ....$
\end{itemize}

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Welcome to TeX.SE! – Mico Mar 28 at 15:56
Welcome to TeX.SX! A tip: If you indent lines by 4 spaces, they'll be marked as a code sample. You can also highlight the code and click the "code" button (with "{}" on it). – Thorsten Mar 28 at 15:58
@Thorsten: Now why on Earth would anyone think that a fuzzy grayed-out {} means "code"? – jamesqf Mar 28 at 17:58
@jamesqf Hover the mouse over the symbol and read the tooltip ... – Thorsten Mar 28 at 18:05
@jamesqf Quite a few programming languages (including TeX!) use braces as delimiters. – Lambda Fairy Mar 29 at 2:10