Rotate a Circle Around the X/Y Axis - Cylindrical Shells

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Homework Statement


Rotate the region bound by the given curve by about the x and y axis. Find the volume through the cylindrical method.
x^2 + (y-1)^2 = 1


Homework Equations


Cylindrical method: ∫2∏xf(x)dx
Slice Method: ∫A(x)dx


The Attempt at a Solution


x^2 + (y-1)^2 = 1
x = √(2y - y^2)

∫2∏x(√(1-x^2)+1)dx from -1 to 1
But this simplifies to 0... What am I doing wrong?
 
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Help, please?
 
What do you mean by rotation "about the x and y axis". I know how to rotate around a single axis but not two.
 
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