[tex]\displaystyle\int_{x=0}^{x=4}\int_{y=x}^{y=2x}\int_{z=0}^{z=y}2xyz\,\mathrm dz\,\mathrm dy\,\mathrm dx[/tex]
[tex]2xy\displaystyle\int_0^yz\,\mathrm dz=2xy\left[\frac{z^2}2\right]\bigg|_{z=0}^{z=y}=xy^3[/tex]
[tex]x\displaystyle\int_x^{2x}y^3\,\mathrm dy=\frac{15}4x^5[/tex]
[tex]\displaystyle\frac{15}4\int_0^4x^5\,\mathrm dx=\dfrac{15}{24}4^6=2560[/tex]
