[Tex/LaTex] size and location of cube root symbol

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Closed 9 years ago.

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Nice-looking p-th roots

On math.stackexchange I wanted the cube root of a fraction in display mode, and used $$\sqrt[3]{\frac ab}$$ to get it. The 3 comes out very small and low in the root sign. I also thought of $$^3\sqrt{\frac ab}$$ but the 3 comes out too far to the left.

Answer 1

You can use \leftroot (for horizontal shifting), and/or \uproot (for vertical shifting) from the amsmath package; using \scriptstyle you can increase the size of the index (not sure if this is a good idea); preferable to use a superscript instead of the root:

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\[ 
\sqrt[3]{\frac{a}{b}}\qquad \sqrt[\leftroot{-1}\uproot{2}\scriptstyle 3]{\frac{a}{b}}\qquad
\Bigl(\frac{a}{b}\Bigr)^{1/3} 
\]

\end{document}