2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/71023We introduce a measure of discrepancy of Hermitian matrices and establish an inequality between the second singular value of a Hermitian matrix and its discrepancy. These results are applied to answer two questions of Fan Chung about graph eigenvalues.22 pages, accepted in Discrete Math. Rev 2 - some typos corrected, thanks Herbert WilfCombinatoricsCommutative Algebra05C50; 15A18text