# Big floor symbols for fraction

When I write

\lfloor\dfrac{1}{2}\rfloor


the floors come out too short to cover the fraction. How can I lengthen the floor symbols?

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You could use \left...\right for stretchable delimiters, or perhaps one of the pairs of the \bigl...\bigr family of commands:

\documentclass{article}
\usepackage{amsmath}

\begin{document}

$\Bigl\lfloor\dfrac{1}{2}\Bigr\rfloor\qquad \left\lfloor\dfrac{1}{2}\right\rfloor$

\end{document}


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