WP-QuickLaTeX rending problem on WordPress hosted by bluehost

I came across the problem when trying to using QuickLatex on bluehost, but it does not seem to work for me as when I use it in the short code block with the following text.

[latexpage]

\[ R =  \left( 1 + {r \over f} \right)^{f}  -1 \]

and resulting web page shows