$$\int_0^2 \int_1^3 \int_0^1 xye^{xz} \,dz \,dy \,dx$$
$$\int_0^2 \int_1^3 y \int_0^1 xe^{xz} \,dz \,dy \,dx$$
$$\int_0^2 \int_1^3 y \, \left[ e^{xz} \right]_{z=0}^1\, \,dy \,dx$$
$$\int_0^2 \left[ e^{xz} \right]_{z=0}^1 \int_1^3 y \,dy \,dx$$
$$\int_0^2 \left[ e^{xz} \right]_{z=0}^1 \left[ {1\over2}y^2 \right]_{y=1}^3 \,dx$$
$$\left[ {1\over2}y^2 \right]_{y=1}^3 \int_0^2 \left[ e^{xz} \right]_{z=0}^1 \,dx$$
$$ \dots = 4e^2-12 $$
Grüße,
M.B.