the point of intersection with the x-axis is x= 0 and x=4.
what i did was
find the volume of the cylinder of radius 4, height 6 - (pi) integrate (6-y)^2
= pi( 96) - pi integrate ( 6- 4x + x^2)^2
but i could not get the answer.
should it not be 6- y for the second part of my equation?