Thêm đường cong có dấu mũi tên

Mặc dù không thích mấy cái tọa độ lộn xộn của Geobra, nhưng vì lười vẽ lại nên dùng code của chú. Chỉ thêm cái đường cong thôi.

Code

\documentclass[12pt]{report}
\usepackage{tikz}
\usetikzlibrary{decorations.markings}
\begin{document}
\begin{figure}[!htp]
\centering
\definecolor{xdxdff}{rgb}{0.49019607843137253,0.49019607843137253,1.}
\definecolor{ududff}{rgb}{0.30196078431372547,0.30196078431372547,1.}
\definecolor{ffqqqq}{rgb}{1.,0.,0.}
\definecolor{ffffqq}{rgb}{1.,1.,0.}
\begin{tikzpicture}[line cap=round,line join=round,x=1.0cm,y=1.0cm, decoration={
    markings,
    mark=at position 0.5cm with {\arrow[red]{latex};},
	mark=at position 1.0cm with {\arrow[red]{latex};},
	mark=at position 1.5cm with {\arrow[red]{latex};},
	mark=at position 2.0cm with {\arrow[red]{latex};},
	mark=at position 2.5cm with {\arrow[red]{latex};},
	mark=at position 3.0cm with {\arrow[red]{latex};},
    mark=at position 3.5cm with {\arrow[red]{latex};}}]
    \begin{scriptsize}
\draw[fill=blue] (7.795694527149545,2.3942593695327266) -- (8.88613566463769,2.4238958169046656) -- (7.459977100709584,0.) -- cycle;
\draw [line width=1pt] (9.,4.)-- (11.,0.);
\draw [line width=1pt] (6.,0.)-- (11.,0.);
\draw [line width=1pt] (9.,4.)-- (6.,0.);
\draw [line width=1pt] (6.993974005212116,1.325298673616154)-- (7.459977100709584,0.);
\draw [line width=1pt] (9.105544674472783,0.8551213965837519)-- (7.459977100709584,0.);
\draw [line width=1pt] (7.795694527149545,2.3942593695327266)-- (7.459977100709584,0.);
\draw [line width=1pt] (7.459977100709584,0.)-- (8.88613566463769,2.4238958169046656);
\draw [line width=1pt] (7.795694527149545,2.3942593695327266)-- (8.88613566463769,2.4238958169046656);
\draw [line width=1pt] (8.88613566463769,2.4238958169046656)-- (9.105544674472783,0.8551213965837519);
\draw [line width=1pt] (9.105544674472783,0.8551213965837519)-- (9.35786503578314,0.);
\draw [line width=1pt] (9.105544674472783,0.8551213965837519)-- (11.,0.);
\draw [line width=1pt] (9.105544674472783,0.8551213965837519)-- (10.,2.);
\draw [line width=1pt] (8.88613566463769,2.4238958169046656)-- (10.,2.);
\draw [line width=1pt] (8.88613566463769,2.4238958169046656)-- (9.,4.);
\draw [line width=1pt] (7.795694527149545,2.3942593695327266)-- (8.88613566463769,2.4238958169046656);
\draw [line width=1pt] (8.88613566463769,2.4238958169046656)-- (7.459977100709584,0.);
\draw [line width=1pt] (7.459977100709584,0.)-- (7.795694527149545,2.3942593695327266);
\draw [fill=ffffqq] (6.,0.) circle (2.5pt);
\draw[color=black] (5.935084482355688,-0.3) node {$B$};
\draw [fill=ffqqqq] (11.,0.) circle (2.5pt);
\draw[color=black] (10.981491708562828,-0.3) node {$C$};
\draw [fill=ududff] (9.,4.) circle (2.5pt);
\draw[color=black] (9.072633322997518,4.206594021814795) node[above] {$A$};
\draw [fill=ffffqq] (6.993974005212116,1.325298673616154) circle (2.5pt);
\draw [fill=ffffqq] (7.795694527149545,2.3942593695327266) circle (2.5pt);
\draw [fill=ududff] (8.88613566463769,2.4238958169046656) circle (2.5pt);
\draw [fill=ffqqqq] (7.459977100709584,0.) circle (2.5pt);
\draw [fill=ffqqqq] (9.35786503578314,0.) circle (2.5pt);
\draw [fill=ududff] (9.105544674472783,0.8551213965837519) circle (2.5pt);
\draw [fill=xdxdff] (10.,2.) circle (2.5pt);
\draw [postaction=decorate, dashed, line width=1pt, color=red] (11,1.2) to [out=-180, in=0] (9,0.5) to [out=-180, in=-60] (7.9,1.2);
\end{scriptsize}
\end{tikzpicture}
\end{figure}
\end{document}

Chú ý: Phải khai báo thư viện \usetikzlibrary{decorations.markings}

Nếu muốn dùng dấu mũi tên kiểu steath thì thay chữ latex bằng steath

Màu đang dùng là magenta!50

Dùng pattern kẻ sọc

Hình này vẽ như bình thường, riêng chỗ hình chữ nhất thì mình khai báo thêm option pattern= dots để cho Tikz fill hình chữ nhật bằng những dấu chấm. Ngoài ra còn có các kiểu khác: dots, grid, crosshatch,…

Xem thêm các pattern ở đây Tikz-PGF (trang 217)

Code

\documentclass{report}
\usepackage{tikz}
\usetikzlibrary{patterns}
\begin{document}
   \begin{tikzpicture}
      \draw[->] (-0.6,0) -- (5,0) node[below]{$x$};
      \draw[->] (0,-0.6) -- (0,4) node[left]{$y$};
      \draw (0,0) node[below left]{$O$};
      \draw[dashed] (1,0) node[below]{$a_1$} -- (1,3);
      \draw[dashed] (2,0) node[below]{$a_2$} -- (2,2.5);
      \draw[dashed] (3,0) node[below]{$b_1$} -- (3,3);
      \draw[dashed] (4,0) node[below]{$b_2$} -- (4,2.5);
      \draw[dashed] (0,1.5) node[left]{$c_1$} -- (4,1.5);
      \draw[dashed] (0,2) node[left]{$c_2$} -- (3,2);
      \draw[dashed] (0,2.5) node[left]{$d_1$} -- (4,2.5);
      \draw[dashed] (0,3) node[left]{$d_2$} -- (3,3);
      \draw[pattern=crosshatch] (1,2) rectangle (3,3);
      \draw[pattern=dots] (2,1.5) rectangle (4,2.5); 
   \end{tikzpicture}
\end{document}

Chú ý khai báo \usetikzlibrary{patterns}

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