Past exam of the mathematics course of the University of Cambridge 2004 iii Paper 31 4 e Solution Created 2026-10-03 Updated 2026-10-14
For , the two variational comparisons agree. Outside that interval the finite-buffer fiber is empty, since its queue workload always lies in . The finite-buffer workload rate truncation is thereforeEquivalently this is J for and infinity above B, since J already assigns infinity to negative queue workloads. Together with the contracted LDP from the first part, this proves the requested principle. The rate is good by contraction; alternatively its finite sublevel sets are the compact sets .