problem compiling some 'math' using LuaLaTeX

Question

Have a couple of documents with the following sort of construct:

\begin{equation}
y=\sqrt[n]{\prod_{i=1}^{n} x_{i}}
\end{equation}

Compiles/renders fine using 'standard' LaTeX, but fails miserably using LuaLaTeX. (I'm using MikTeX 2.9 for both).

Any suggestions? Here is a MWE to 'play with'. As noted, the problem arises because of the 'product' inside the square root. luaLaTeX seems to be having problems handling 'big expressions' nested within the square-root construct.

Thanks in advance.

\documentclass{article}
\usepackage{amsmath}

\begin{document}

This equation is properly rendered using a standard \LaTeX. However, it is not when compiled using lua\LaTeX.

\begin{equation*}
y=\sqrt[n]{\prod_{i=1}^{n} x_{i}}
\end{equation*}

This simpler expression compiles correctly.

\begin{equation*}
y=\sqrt[n]{x}
\end{equation*}

\end{document} 

---

OK, tried

\usepackage{unicode-math}
\setmathfont{Asana Math}

and it compiles fine, except I don't particular want to use Asana Math (given everything else is CM). So, for my (never-ending) edification, the * trick* (solution) hinges on using unicode?

It seems as if the problem (as originally described) relates specifically to the \prod operator. For example,

\begin{equation}
y=\sqrt[n]{\frac{x^n-y^n}{1+u^{2n}}}
\end{equation}

compiles/renders fine.

---

Here is what the PDF I'm rendering before adding the suggested unicode-math package.

http://canuck.dnr.cornell.edu/misc/mah-example.pdf

Answer 1

With LuaLaTeX try

\documentclass{article}
\usepackage{amsmath}
\usepackage{unicode-math}
\setmathfont{Latin Modern Math}

...