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## Homework Statement

the directions are:

compute the volume of the solid formed by revolving the given region about the line

region bounded by y=2x, y=2 and x=0 about (a) the y-axis; (b) x=1

## Homework Equations

V=∫A(x)dx,a,b

## The Attempt at a Solution

From what my teacher showed in class this is how i think it is worked out

(a)

V=∫A(x)dx,0,2

=∫(pi)[r(x)]^2,0,2

=∫(pi)[2x-2]^2,0,2

=∫(pi)[4x^2-a],0,2

=(8(pi))/3

so i am not sure if this is right or if i have to times(8(pi))/3 by 1/3 because the volume of a cone is (1/3)(pi)(r^2)(h)

and i don't know where to begin on (b), i think when it is revolved it will be Cylinder with a cut out. please help