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\title{Git samen - \LaTeX formules}
\begin{document}
Formule A:\\
$$\forall x \in A : (P(x) \Rightarrow Q (x))$$

Formule B: \\
\[ \int_{a}^{b}u\frac{d^2v}{dx^2}dx = u\frac{dv}{dx} \Big|_{a}^{b} - \int_{a}^{b}\frac{du}{dx}\frac{dv}{dx}dx.\]

Formule C: \\
\[e^x = \sum_{n=0}^{\infty} \frac{x^n}{n!} \ where \ n! =  \prod_{i=1}^{n} i, \ \overline{U_\alpha} \ = \ \bigcap_{\alpha} U_\alpha\]
\end{document}
