I have an area delimited by y=sqrt(x), y=0 and x=4. I want to rotate this area around the y axis to get the solid of revolution, but instead I get another solid. I am using: VolumeOfRevolution(sqrt(x),x=0..4,axis='vertical','distancefromaxis'=0,'output'='plot'); If you look at the resulting solid, you'll see that is the product of rotating the area limited by y^2(reverse function of sqrt(x)), x=0 and y=2 around the y axis, but not of the area delimited by y=sqrt(x), y=0 and x=4. How can I plot it with VolumeOfRevolution command?