答案1
这是一个快速写下的答案(抱歉,我快要跳了),只涉及问题的主要部分:添加“水印”。它没有讨论如何改进图形的布局/排列,这当然是可能的minipages
,特别是没有\\
所有这些\vspace
命令。
\documentclass[12pt]{book}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{graphicx}
\usepackage{tikz} %Encendido
\usepackage{tikzpeople}
\usepackage{pgfplots}
\pgfplotsset{compat=1.16}
\begin{document}
\textbf{Determinar cuando una gr\'afica corresponde a una funci\'on}
De las gr\'aficas que se presentan a continuaci\'on, se determina las relaciones
que corresponden y no a una funci\'on.\\
\noindent
\begin{minipage}{0.48\textwidth}
Corresponde a una funci\'on\\
\begin{tikzpicture}[scale=0.6,local bounding box=TL]
\draw [color=gray] (-3.5,-3.5) grid (3.5,3.5);
\draw [latex-latex, very thick] (-4,0) -- (4,0) node [below] {$x$};
\draw [latex-latex, very thick] (0,-4) -- (0,4) node [right] {$y$};
\draw[latex-latex,domain=-2:2,variable=\x,color=blue, line width=1.2pt] plot ({\x},{\x * \x -1});
\draw [line width=1.2pt,dashed,red] (-1,-3)-- (-1,3);
\fill [fill=red] (-1,0) circle (3.5pt);
\node[overlay,graduate,shield,minimum size=1cm,yshift=4mm] at (TL.south east){};
\end{tikzpicture}
\vspace{0.7cm}
\rule{6cm}{0.1mm}\\
\rule{6cm}{0.1mm}
\end{minipage} \hfill
\begin{minipage}{0.48\textwidth}
Corresponde a una funci\'on\\
\begin{tikzpicture}[scale=0.6]
\draw [color=gray] (-3.5,-3.5) grid (3.5,3.5);
\draw [latex-latex, very thick] (-4,0) -- (4,0) node [below] {$x$};
\draw [latex-latex, very thick] (0,-4) -- (0,4) node [right] {$y$};
\draw[latex-latex,domain=-2.5:1.28,variable=\x,color=blue, line width=1.2pt] plot ({\x},{\x * \x * \x * \x +2 * \x * \x * \x -\x * \x - \x -1});
\draw [line width=1.2pt,dashed,red] (-1,-3)-- (-1,3);
\fill [fill=red] (-1,-2) circle (3.5pt);
\end{tikzpicture}
\vspace{0.7cm}
\rule{6cm}{0.1mm}\\
\rule{6cm}{0.1mm}
\end{minipage}
\vspace{1cm}
\noindent
\begin{minipage}{0.48\textwidth}
No corresponde a una funci\'on\\
\begin{tikzpicture}[scale=0.6,local bounding box=BL]
\draw [color=gray] (-3.5,-3.5) grid (3.5,3.5);
\draw [latex-latex, very thick] (-4,0) -- (4,0) node [below] {$x$};
\draw [latex-latex, very thick] (0,-4) -- (0,4) node [right] {$y$};
\draw [line width=1.5pt,color=blue] (2,-2) -- (-2,-2)-- (2,2) -- (-2,2);
\draw [line width=1.2pt,dashed,red] (-1,-3)-- (-1,3);
\fill [fill=red] (-1,2) circle (3.5pt);
\fill [fill=red] (-1,-1) circle (3.5pt);
\fill [fill=red] (-1,-2) circle (3.5pt);
\node[overlay,graduate,shield,minimum size=1cm,yshift=4mm] at (BL.south east){};
\end{tikzpicture}
\vspace{0.7cm}
\rule{6cm}{0.1mm}\\
\rule{6cm}{0.1mm}
\end{minipage} \hfill
\begin{minipage}{0.48\textwidth}
No corresponde a una funci\'on\\
\begin{tikzpicture}[scale=0.6]
\draw [color=gray] (-0.5,-1.5) grid (6.5,5.5);
\draw [latex-latex, very thick] (-1,0) -- (7,0) node [below] {$x$};
\draw [latex-latex, very thick] (0,-2) -- (0,6) node [right] {$y$};
\draw [line width=1.2pt,dashed,red] (2.,-1)-- (2.,5);
\draw [line width=1.5pt,blue] (3,2) circle (2cm);
\fill [fill=red] (2,0.28) circle (3.5pt);
\fill [fill=red] (2,3.72) circle (3.5pt);
\end{tikzpicture}
\vspace{0.7cm}
\rule{6cm}{0.1mm}\\
\rule{6cm}{0.1mm}
\end{minipage}
\end{document}