\documentclass{article}
\usepackage{ifthen}
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\begin{document}
$gain=\frac{m0x+c0}{m1x+c1}$
\pagebreak

$gain=\frac{c0}{m1x+c1}$
\pagebreak

$\frac{m0x+c0}{c1}$
\pagebreak

$gain = a \cdot 2^{m \cdot x}$
\pagebreak

$log_{2}{10^{\frac{1}{20}}}$
\pagebreak

$LP = \frac{1\mathrm{m}}{D}$
\pagebreak

\end{document}
