正弦函数图

Question

我想要绘制 $y = \sin^2(x) + \cos(x)$。

\documentclass[10pt]{amsart}

\usepackage{tikz}
\usetikzlibrary{calc,intersections}

\usepackage{pgfplots}
\pgfplotsset{compat=1.11}


\begin{document}

\begin{tikzpicture}
\begin{axis}[width=4in,axis on top,clip=false,
    axis lines=middle,
    xmin=-6.2832,xmax=7.4259,
    ymin=-1,ymax=1.25,
    restrict y to domain=-1:1.25,
    ticklabel style={font=\tiny},
    xtick={-1.0472, 1.0472},
    xticklabels={\makebox[0pt][r]{$\scriptstyle-$}$\scriptstyle\dfrac{\pi}{3}$, $\scriptstyle\dfrac{\pi}{3}$},
    xlabel=$x$,ylabel=$y$,
    ytick={-1, 1.25},
    yticklabels={$\scriptstyle-1$, $\scriptstyle\dfrac{5}{4}$},
    axis line style={latex-latex},
    enlargelimits={abs=0.25cm},
    xlabel style={at={(ticklabel* cs:1)},anchor=north west},
    ylabel style={at={(ticklabel* cs:1)},anchor=south west}
]
\addplot[samples=201,domain=-6.2832:6.2832, dashed] {(sin(deg(x)))^2 + cos(deg(2*x))} ;


\end{axis}
\end{tikzpicture}

\end{document}

Answer 1

第 29 行的“2”太多了，应该是cos(deg(x))：

\documentclass[10pt]{amsart}

\usepackage{tikz}
\usetikzlibrary{calc,intersections}

\usepackage{pgfplots}
\pgfplotsset{compat=1.11}


\begin{document}

    \begin{tikzpicture}
    \begin{axis}[width=4in,axis on top,clip=false,
    axis lines=middle,
    xmin=-6.2832,xmax=7.4259,
    ymin=-1,ymax=1.25,
    restrict y to domain=-1:1.25,
    ticklabel style={font=\tiny},
    xtick={-1.0472, 1.0472},
    xticklabels={\makebox[0pt][r]{$\scriptstyle-$}$\scriptstyle\dfrac{\pi}{3}$, $\scriptstyle\dfrac{\pi}{3}$},
    xlabel=$x$,ylabel=$y$,
    ytick={-1, 1.25},
    yticklabels={$\scriptstyle-1$, $\scriptstyle\dfrac{5}{4}$},
    axis line style={latex-latex},
    enlargelimits={abs=0.25cm},
    xlabel style={at={(ticklabel* cs:1)},anchor=north west},
    ylabel style={at={(ticklabel* cs:1)},anchor=south west}
    ]
    \addplot[samples=201,domain=-6.2832:6.2832, dashed] {(sin(deg(x)))^2 + cos(deg(x))} ;


    \end{axis}
    \end{tikzpicture}

\end{document}