Prima di ogni figura ricordare di mettere
\documentclass[usenames,dvipsnames]{article}
\usepackage{pgfplots}
Prima figura
codice prima figura
\begin{tikzpicture}
\begin{axis}[
scale=0.49,
axis x line=center,
axis y line=center,
xmin = 0,
xmax = 2.9,
ymin = 0,
ymax = 5.9,
xlabel = {$x$},
ylabel = {$y$},
extra x ticks = {0},
extra x tick label = {$O$},
]
\addplot[very thick,samples=100,Red,domain=0:1] {4-pi*x*x};
\addplot[very thick,samples=50,Red,domain=1:1.414] {23.473*x^2-53.229*x+30.6147};
\addplot[very thick,samples=50,Red,domain=1.414:5] {4*(1-exp(-3.29*(x-1.414)))+2*pi-4};
\addplot[no marks] coordinates {(2,2)} node {\fbox{a}};
\end{axis}
\end{tikzpicture}
seconda figura
codice seconda figura
\begin{tikzpicture}
\begin{axis}[
scale=0.49,
axis x line=center,
axis y line=center,
xmin = 0,
xmax = 2.9,
ymin = 0,
ymax = 5.9,
xlabel = {$x$},
ylabel = {$y$},
extra x ticks = {0},
extra x tick label = {$O$},
]
\addplot[very thick,samples=100,Red,domain=0:1] {(4-pi*x*x-0.438)*1.123};
\addplot[very thick,samples=50,Red,domain=1:1.414] {(23.473*x^2-53.229*x+30.6147-0.438)*1.123};
\addplot[very thick,samples=50,Red,domain=1.414:5] {(4*(1-exp(-3.29*(x-1.414)))+2*pi-4-0.438)*1.123};
\addplot[no marks] coordinates {(2,2)} node {\fbox{b}};
\end{axis}
\end{tikzpicture}
terza figura
codice terza figura
\begin{tikzpicture}
\begin{axis}[
axis equal image,
scale=0.65,
axis x line=center,
axis y line=center,
xmin = -3.9,
xmax = 3.9,
ymin = -3.9,
ymax = 3.9,
xlabel = {$x$},
ylabel = {$y$},
extra x ticks = {0},
extra x tick label = {$\hspace{-0.6cm}O$},
colormap={redyellow}{rgb255(0cm)=(148,1,1); rgb255(1cm)=(242,230,0)}
]
\addplot[very thick,samples=100,mesh,point meta=x] {3/2*x^2+2/3*x-2};
\addplot[no marks] coordinates {(1,-3)} node[right] {\fbox{c}};
\end{axis}
\end{tikzpicture}%
quarta figura
codice quarta figura
\begin{tikzpicture} % h(x)
\begin{axis}[
axis equal image,
scale=0.65,
axis x line=center,
axis y line=center,
xmin = -3.9,
xmax = 3.9,
ymin = -3.9,
ymax = 3.9,
xlabel = {$x$},
ylabel = {$y$},
extra x ticks = {0},
extra x tick label = {$\hspace{-0.6cm}O$},
colormap={redyellow}{rgb255(0cm)=(148,1,1); rgb255(1cm)=(242,230,0)}
]
\addplot[very thick,samples=100,mesh,point meta=x] {(-x^3/2-x^2/3+2*x)/1.5+2};
\addplot[no marks] coordinates {(0.5,-3)} node[right] {\fbox{d}};
\end{axis}
\end{tikzpicture}
quinta figura
codice quinta figura
\begin{tikzpicture}
\begin{axis}[
scale=0.49,
axis x line=center,
axis y line=center,
xmin = 0,
xmax = 2.9,
ymin = 0,
ymax = 5.9,
xlabel = {$x$},
ylabel = {$y$},
extra x ticks = {0},
extra x tick label = {$O$},
]
\addplot[very thick,samples=100,domain=0:1.128,Red] {4-pi*x*x};
\addplot[very thick,samples=100,domain=1.128:3,Red] {pi*x*x-4};
\addplot[no marks] coordinates {(2,2)} node {\fbox{e}};
\end{axis}
\end{tikzpicture}