find the volume of the solid generated by revolving the regi

find the volume of the solid generated by revolving the region bounded by the graphs of the equations y=10x^2, y=0, x=2, about the line y=40

sol Radius = ( 2 - sqrt(y/2) ) Volume = integral [0,8]: pi*Radius^2 = integral [0,8]: pi*(4 - 4*sqrt(y/2) + y/2) = [0,8] pi * (4y - (4/3)*y^(3/2) + (1/4)*y^2) = (48 - 16*sqrt(2)) * pi