How do I draw a tilde in math mode? [duplicate]

Question

Possible Duplicate:
How does one insert a backslash or a tilde into LaTeX?

I have tried using \text{\~{}} to draw a tilde in math mode. However, this only produces a superscript tilde.

I have looked around at many pages such as this one: http://www.artofproblemsolving.com/Wiki/index.php/LaTeX:Symbols

and surprisingly, I can't find where to draw a tilde in math mode (not under or above a character - just a single tilde character). If I just use ~, then nothing appears.

Answer 1

\documentclass{article}
\usepackage{amsmath}
\usepackage{amssymb}

\begin{document}
$\backsim\ \sim\ \thicksim$
\end{document}

Answer 2

Is \sim an option for you? It looks like a tilde.