Lasciamo perdere, e mettiamoci soltanto un “teorema”: ci sono troppe variabili in gioco, altrimenti. Ecco l’esempio minimo… minimo per modo di dire però, perché debbo riempire il preambolo di tutto quello che mi sta mandando al manicomio!
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\colorbox{yellow!30}{VOCABOLARIO} \\ \colorbox{yellow!30}{DI} \\ \colorbox{yellow!30}{TEORIA DELL'INTEGRAZIONE}
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{\textsl{\addfontfeatures{Color=Red} Andrea Carpignani}\par}
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{\scriptsize[versione del~\today]}
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Mathematiker sind wie Franzosen: Wenn du ihnen etwas sagst, übersetzen sie es gleich in ihre eigene Sprache, und sofort bedeutet es etwas ganz anderes.
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{\frakfont\bfseries\addfontfeatures{Color=DarkBlue} Johannes Wolfgang von~Goethe}
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\begin{teorema}[fondamentale del calcolo integrale]
Sia~$f$ una funzione reale definita e continua su un intervallo~$U$ di~$\rr$ (non ridotto ad un punto), e sia~$x_0$ un punto di~$U$. Poniamo
\[
F(x) = \int_{x_0}^x f(t)\d t.
\]
Allora~$F$ è una primitiva di~$f$.
\end{teorema}
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Ciao e grazie,
Andrea
PS: Ho notato soltanto dopo che, quando applico le modifiche che mi hai consigliato, l’impaginazione della pagina cambia. Non ho idea del motivo!