(1) Select u and v considering LIATE:

u=xv=e4xu=1v=14e4xuv=xe4xoriginaluv=14e4xfinal

(2) Apply IBP formula uvuv and compute integral:

uvuvx4e4x|030314e4xdxx4e4x116e4x|03(x4116)e4x|03e12(34116)1(116)1116e12+116