The volume of the solid obtained by rotating the region enclosed by $y=x^2, x=y^2$
about the line $x=−5$
can be computed using the method of disks or washers via an integral
I am doing it like $V=\int_0^1\pi(5+\sqrt y)^2 - (5+y^2)^2\,\text{d}y$.
but I am not getting a correct answer, so anybody could explain what is wrong with the formula