Answer
$\dfrac{1024 \pi}{15}$
Work Step by Step
The Washer method to compute the volume of revolution: When the function $f(x)$ is continuous and $f(x) \geq g(x) \geq 0$ on the interval $[m,n]$, then the volume of a solid obtained by rotating the region under $y=f(x)$ over an interval $[m,n]$ about the x-axis is given by:
$V=\pi \int_{m}^{n} (R^2_{outside}-R^2_{inside}) \ dy$
$V=\pi \int_0^2 [(8)^2 -(x^2+4)^2] \ dx \\ = \pi \int_0^2 [ -x^4 -8x^2+48 ] \ dx \\=\pi [-\dfrac{x^5}{5} -\dfrac{8x^3}{3}+48 x]_0^2 \ dx \\=\pi [-\dfrac{2^5}{5} -\dfrac{8(2^3)}{3}+48(2)] \ dx \\=\dfrac{1024 \pi}{15}$
