całki

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\begin{document}
\begin{equation*}
\begin{multlined}
\int_{-1}^{2} (x^2 -2x) = \left|
\begin{array}{c}
f(x)=x^2-2x\\
\int\! f(x)dx=\frac{x^3}{3}-x^2+C\\
F(x)=\frac{x^3}{3}-x^2
\end{array}
\right| = \Big[\frac{x^3}{3}-x^2\Big]_{-1}^{2} = \\ \Big(\frac{2^3}{3}-2^2\Big) - \Big(\frac{(-1)^3}{3} - (-1)^2\Big) = \Big(\frac{8}{3}-4 \Big)- \Big(-\frac{1}{3}-1\Big) = -\frac{4}{3}+\frac{4}{3}=0
\end{multlined}
\end{equation*}
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