In[]:=
TicTacUFO::usage=​​"To obtain the volume, the disk method is used:
V
i
=π[f(x)​
2
]
dx o
V
i
=π[f(y)​
2
]
dy";​​​​​​PlotPiecewise
1-(x-1)^2
,0≤x≤1,{1,1≤x≤6},
1-(x-6)^2
,6≤x≤7,{x,0,7},AspectRatio->Automatic
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F[t_]:=Piecewise
1-(t-1)^2
,0≤t≤1,{1,1≤t≤6},
1-(t-6)^2
,6≤t≤7;​​gr=RevolutionPlot3D[F[t],{t,0,7},RevolutionAxis{1,0,0},MeshNone,AxesFalse,ColorFunction"IslandColors",BoxedFalse]
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V=N
1
∫
0
π
2

1-(x-1)^2

x+
6
∫
1
πx+
7
∫
6
π
2

1-(x-6)^2

x
Out[]=
19.8968
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ResourceFunction["SpinShow"][gr,30]
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