\documentclass[10pt,a4paper]{article} % Packages \usepackage{fancyhdr} % For header and footer \usepackage{multicol} % Allows multicols in tables \usepackage{tabularx} % Intelligent column widths \usepackage{tabulary} % Used in header and footer \usepackage{hhline} % Border under tables \usepackage{graphicx} % For images \usepackage{xcolor} % For hex colours %\usepackage[utf8x]{inputenc} % For unicode character support \usepackage[T1]{fontenc} % Without this we get weird character replacements \usepackage{colortbl} % For coloured tables \usepackage{setspace} % For line height \usepackage{lastpage} % Needed for total page number \usepackage{seqsplit} % Splits long words. %\usepackage{opensans} % Can't make this work so far. Shame. Would be lovely. \usepackage[normalem]{ulem} % For underlining links % Most of the following are not required for the majority % of cheat sheets but are needed for some symbol support. \usepackage{amsmath} % Symbols \usepackage{MnSymbol} % Symbols \usepackage{wasysym} % Symbols %\usepackage[english,german,french,spanish,italian]{babel} % Languages % Document Info \author{starlight (starlighttx)} \pdfinfo{ /Title (la-parabola.pdf) /Creator (Cheatography) /Author (starlight (starlighttx)) /Subject (La Parabola Cheat Sheet) } % Lengths and widths \addtolength{\textwidth}{6cm} \addtolength{\textheight}{-1cm} \addtolength{\hoffset}{-3cm} \addtolength{\voffset}{-2cm} \setlength{\tabcolsep}{0.2cm} % Space between columns \setlength{\headsep}{-12pt} % Reduce space between header and content \setlength{\headheight}{85pt} % If less, LaTeX automatically increases it \renewcommand{\footrulewidth}{0pt} % Remove footer line \renewcommand{\headrulewidth}{0pt} % Remove header line \renewcommand{\seqinsert}{\ifmmode\allowbreak\else\-\fi} % Hyphens in seqsplit % This two commands together give roughly % the right line height in the tables \renewcommand{\arraystretch}{1.3} \onehalfspacing % Commands \newcommand{\SetRowColor}[1]{\noalign{\gdef\RowColorName{#1}}\rowcolor{\RowColorName}} % Shortcut for row colour \newcommand{\mymulticolumn}[3]{\multicolumn{#1}{>{\columncolor{\RowColorName}}#2}{#3}} % For coloured multi-cols \newcolumntype{x}[1]{>{\raggedright}p{#1}} % New column types for ragged-right paragraph columns \newcommand{\tn}{\tabularnewline} % Required as custom column type in use % Font and Colours \definecolor{HeadBackground}{HTML}{333333} \definecolor{FootBackground}{HTML}{666666} \definecolor{TextColor}{HTML}{333333} \definecolor{DarkBackground}{HTML}{7D52A3} \definecolor{LightBackground}{HTML}{F6F4F9} \renewcommand{\familydefault}{\sfdefault} \color{TextColor} % Header and Footer \pagestyle{fancy} \fancyhead{} % Set header to blank \fancyfoot{} % Set footer to blank \fancyhead[L]{ \noindent \begin{multicols}{3} \begin{tabulary}{5.8cm}{C} \SetRowColor{DarkBackground} \vspace{-7pt} {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}} } \end{tabulary} \columnbreak \begin{tabulary}{11cm}{L} \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{La Parabola Cheat Sheet}}}} \\ \normalsize{by \textcolor{DarkBackground}{starlight (starlighttx)} via \textcolor{DarkBackground}{\uline{cheatography.com/211272/cs/45738/}}} \end{tabulary} \end{multicols}} \fancyfoot[L]{ \footnotesize \noindent \begin{multicols}{3} \begin{tabulary}{5.8cm}{LL} \SetRowColor{FootBackground} \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}} \\ \vspace{-2pt}starlight (starlighttx) \\ \uline{cheatography.com/starlighttx} \\ \end{tabulary} \vfill \columnbreak \begin{tabulary}{5.8cm}{L} \SetRowColor{FootBackground} \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}} \\ \vspace{-2pt}Published 23rd February, 2025.\\ Updated 23rd February, 2025.\\ Page {\thepage} of \pageref{LastPage}. \end{tabulary} \vfill \columnbreak \begin{tabulary}{5.8cm}{L} \SetRowColor{FootBackground} \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}} \\ \SetRowColor{white} \vspace{-5pt} %\includegraphics[width=48px,height=48px]{dave.jpeg} Measure your website readability!\\ www.readability-score.com \end{tabulary} \end{multicols}} \begin{document} \raggedright \raggedcolumns % Set font size to small. Switch to any value % from this page to resize cheat sheet text: % www.emerson.emory.edu/services/latex/latex_169.html \footnotesize % Small font. \begin{multicols*}{3} \begin{tabularx}{5.377cm}{x{1.74195 cm} x{3.23505 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{{\bf{La parabola}}}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{2}{x{5.377cm}}{La parabola è una delle coniche. Fissati nel piano un punto {\emph{F}} (fuoco) e una retta {\emph{d}} (direttrice), si chiama parabola la curva luogo geometrico dei punti equidistanti da {\emph{F}} e da {\emph{d}}} \tn % Row Count 4 (+ 4) % Row 1 \SetRowColor{white} EQUAZIONE & y= ax\textasciicircum{}2\textasciicircum{} + bx + c \tn % Row Count 5 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{2.43873 cm} x{2.53827 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{{\bf{Formule generali: parallela all'asse y}}}} \tn % Row 0 \SetRowColor{LightBackground} VERTICE & V(-b/2a ; -Δ/4a) \tn % Row Count 1 (+ 1) % Row 1 \SetRowColor{white} FUOCO & F(-b/2a ; 1-Δ/4a) \tn % Row Count 2 (+ 1) % Row 2 \SetRowColor{LightBackground} DIRETTRICE & y=-(1+Δ/4a) \tn % Row Count 3 (+ 1) % Row 3 \SetRowColor{white} ASSE DI SIMMETRIA & x=-b/2a \tn % Row Count 4 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{2.43873 cm} x{2.53827 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{{\bf{Formule generali: perpendicolare all'asse y}}}} \tn % Row 0 \SetRowColor{LightBackground} EQUAZIONE & x= ay\textasciicircum{}2\textasciicircum{} +by +c \tn % Row Count 1 (+ 1) % Row 1 \SetRowColor{white} VERTICE & V(-Δ/4a ; -b/2a) \tn % Row Count 2 (+ 1) % Row 2 \SetRowColor{LightBackground} FUOCO & F(1-Δ/4a ; -b/2a) \tn % Row Count 3 (+ 1) % Row 3 \SetRowColor{white} DIRETTRICE & x=-(1+Δ/4a) \tn % Row Count 4 (+ 1) % Row 4 \SetRowColor{LightBackground} ASSE DI SIMMETRIA & y= -b/2a \tn % Row Count 5 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{3.68298 cm} x{1.29402 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Parabole congruenti}} \tn % Row 0 \SetRowColor{LightBackground} Date y=ax\textasciicircum{}2\textasciicircum{}+bx+c e y=a\textasciitilde{}1\textasciitilde{}x\textasciicircum{}2\textasciicircum{}+b\textasciitilde{}1\textasciitilde{}x+c\textasciitilde{}1\textasciitilde{}, esse sono congruenti se hanno la stessa apertura & {\bf{|a|=|a\textasciitilde{}1\textasciitilde{}|}} \tn % Row Count 4 (+ 4) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{SEGMENTO PARABOLICO}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/starlighttx_1740320756_segmento parabolico.png}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{2.83689 cm} x{2.14011 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Segmento parabolico}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{2}{x{5.377cm}}{Il segmento parabolico è la parte di piano compresa tra la parabola e la retta secante} \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} Per il teorema di Archimede, l'area del segmento parabolico è i 4/3 di quella del triangolo massimo inscritto al segmento parabolico che ha base AB & A\textasciitilde{}sp\textasciitilde{}=A\textasciitilde{}tm\textasciitilde{}(4/3) \tn % Row Count 9 (+ 7) % Row 2 \SetRowColor{LightBackground} Formula generale & A\textasciitilde{}sp\textasciitilde{}= |a|/6 × |x\textasciitilde{}0\textasciitilde{}-x\textasciitilde{}1\textasciitilde{}|\textasciicircum{}3\textasciicircum{} \tn % Row Count 11 (+ 2) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{RETTA ESTERNA ALLA PARABOLA}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/starlighttx_1740319553_EST.jpg}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Retta esterna alla parabola}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{La retta è esterna alla parabola quando non hanno punti in comune} \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Δ \textless{} 0} \tn % Row Count 3 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{RETTA SECANTE ALLA PARABOLA}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/starlighttx_1740319646_SEC.jpg}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Retta secante alla parabola}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{La retta e la parabola hanno due punti di intersezione distinti} \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Δ\textgreater{}0} \tn % Row Count 3 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{RETTA TANGENTE ALLA PARABOLA}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/starlighttx_1740319810_TAN.jpg}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Retta tangente alla parabola}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{La retta e la parabola hanno un punto di intersezione doppio (= due coincidenti)} \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Δ=0} \tn % Row Count 3 (+ 1) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Punti e parabole}} \tn % Row 0 \SetRowColor{LightBackground} Sistema di equazioni tra fascio di rette e parabola & y-y\textasciitilde{}0\textasciitilde{}=m(x-x\textasciitilde{}0\textasciitilde{}) y=ax\textasciicircum{}2\textasciicircum{}+bx+c \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} Equazione risolvente del sistema di equazioni tra fascio di rette e parabola & ax\textasciicircum{}2\textasciicircum{}+bx+c=m(x-x\textasciitilde{}0\textasciitilde{})+y\textasciitilde{}0\textasciitilde{} \tn % Row Count 7 (+ 4) % Row 2 \SetRowColor{LightBackground} Se il punto è esterno alla parabola, possiamo tracciare due tangenti & con Δ=0, abbiamo soluzioni m\textasciitilde{}1\textasciitilde{} diverso da m\textasciitilde{}2\textasciitilde{} \tn % Row Count 11 (+ 4) % Row 3 \SetRowColor{white} Se il punto appartiene alla parabola, possiamo tracciare una sola tangente & con Δ=0, abbiamo una sola soluzione di m \tn % Row Count 15 (+ 4) % Row 4 \SetRowColor{LightBackground} Se il punto è interno alla parabola, non possiamo tracciare nessuna tangente & con Δ=0, non abbiamo alcuna soluzione \tn % Row Count 19 (+ 4) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{SE IL PUNTO APPARTIENE ALLA PARABOLA}} \tn % Row 0 \SetRowColor{LightBackground} Formula per trovare m (solo nella parabola) & m=2ax\textasciitilde{}0\textasciitilde{}+b, avendo P(x\textasciitilde{}0\textasciitilde{};y\textasciitilde{}0\textasciitilde{}) \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} Formule generali (ogni curva) & x-\textgreater{}(x+x\textasciitilde{}0\textasciitilde{})/2; y-\textgreater{}(y+y\textasciitilde{}0\textasciitilde{})/2; x\textasciicircum{}2\textasciicircum{}-\textgreater{}x×x\textasciitilde{}0\textasciitilde{} \tn % Row Count 6 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{FASCI DI PARABOLE}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/starlighttx_1740321195_fasci.jpg}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{2.04057 cm} x{2.93643 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Fasci di parabole}} \tn % Row 0 \SetRowColor{LightBackground} Equazione & y=ax\textasciicircum{}2\textasciicircum{}+bx+c + k(a\textasciitilde{}1\textasciitilde{}x\textasciicircum{}2\textasciicircum{}+b\textasciitilde{}1\textasciitilde{}x+c) \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} Punti base & sono i punti in comune tra tutte le parabole del fascio \tn % Row Count 5 (+ 3) % Row 2 \SetRowColor{LightBackground} Parabole degeneri algebriche & sono rette passanti per i punti base che si possono ottenere dall'equazione del fascio \tn % Row Count 9 (+ 4) % Row 3 \SetRowColor{white} Parabole degeneri grafiche & sono rette/coppie di rette parallele all'asse y passanti per i punti base. Le possiamo identificare nel grafico, ma non si possono ricavare dall'equazione \tn % Row Count 16 (+ 7) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Fasci di parabole: casi grafici}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{CASO 1: due punti base e una parabola degenere algebrica (+ una coppia di rette passante per punti base -\textgreater{} parabola degenere grafica)} \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{CASO 2: un punto base doppio e una parabola degenere algebrica (+ una retta passante per il punto base -\textgreater{} parabola degenere grafica)} \tn % Row Count 6 (+ 3) % Row 2 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{CASO 3: nessun punto base, ma una parabola degenere algebrica} \tn % Row Count 8 (+ 2) % Row 3 \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{CASO 4: nessun punto base, nessuna degenere, ma congruenti e con stesso asse di simmetria} \tn % Row Count 10 (+ 2) % Row 4 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{CASO 5: un punto base semplice, senza degenere algebrica (+ una una retta passante per il punto base -\textgreater{} parabola degenere grafica)} \tn % Row Count 13 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{3.08574 cm} x{1.89126 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Fasci di parabole: casi algebrici}} \tn % Row 0 \SetRowColor{LightBackground} CASO 1: la y NON dipende dal parametro & es. y=3tx\textasciicircum{}2\textasciicircum{}-x+t \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} CASO 2: anche la y dipende dal parametro & es. {\bf{t}}y=(t-1)x\textasciicircum{}2\textasciicircum{}+tx-2 \tn % Row Count 4 (+ 2) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{LA NORMALE}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/starlighttx_1740322532_normale.png}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{La normale}} \tn % Row 0 \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{La normale è la retta passante per il punto di tangenza che è {\bf{perpendicolare}} alla tangente stessa} \tn % Row Count 3 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} % That's all folks \end{multicols*} \end{document}