Question: How do I plot volume of revolution

How do I plot a volume of revolution? I can plot other volumes using Student[Calculus1]]:-VolumeOfRevolution, but not this one. I get a blank plot. I do get the correct volume from output=value..

How do I plot this using plot3d?

a := 0; b := 1;
f := (x) -> x^2+2;
g := (x) -> 1/2*x+1;
V := int(f(x)^2 - g(x)^2,x=a..b)*Pi;

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