If I compile LaTeX formulas in a pdf such as

\begin{equation}
\operatorname{util} = \overbrace{\alpha A + \beta B}^{\mbox{gains}} \overbrace{- \gamma C - \delta D}^{\mbox{costs}} \overbrace{- \epsilon E - \eta F}^{\mbox{penalties}}
\end{equation} 


\begin{equation}
d = \sqrt{\frac{123}{abc}} \cdot l
\end{equation}


there are imperfections visible or invisible, depending on the level of zoom. If I open the same file with Adobe Reader this does not happen.


In the image I attached, you can see at the attachment of the "pieces" of the horizontal curly brackets there are imperfections, and the same holds for the square root symbol.

I know this is a minor problem, but just to let you aware of it...

Reproducible: Always

Steps to Reproduce:
1. compile the pdf file with pdflatex
2. open it
3. zoom in and out to see the imperfections appear and disappear
Actual Results:  
imperfections due to zooming interpolation (I guess) appear

Expected Results:  
Perfect symbols