\documentclass{article}
\usepackage{iftex}
\usepackage{ifthen}
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\usepackage[utf8]{inputenc}
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\begin{document}
$ \sum f(x) = \sum (c_0 + c_1 \cdot x + c_2 \cdot x^2 + c_3 \cdot x^3 + c_4 \cdot
x^4)$
\pagebreak

$\int_0^\pi e^x dx$
\pagebreak

$x=1.5$
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$ e^x = e^1.5 * (1 + x + \frac{1}{2} x^2 + \frac{1}{6}x^3 + \frac{1}{24}x^4) $
\pagebreak

$x^2 + x$
\pagebreak

\end{document}
