Khan Academy on a Stick : Disc method with outer and inner function boundaries

Khan Academy on a Stick

Solid of revolution volume

Disc method: function rotated about x-axis
Disc method (rotating f(x) about x axis)
Volume of a sphere
Disc method with outer and inner function boundaries
Shell method to rotate around y-axis
Disk method: rotating x=f(y) around the y-axis
Shell method around a non-axis line
Shell method around a non-axis line 2

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